ubelt package

Submodules

• ubelt.orderedset module
• ubelt.progiter module
• ubelt.timerit module
• ubelt.util_arg module
• ubelt.util_cache module
• ubelt.util_cmd module
• ubelt.util_colors module
• ubelt.util_const module
• ubelt.util_dict module
• ubelt.util_download module
• ubelt.util_download_manager module
• ubelt.util_format module
• ubelt.util_func module
• ubelt.util_futures module
• ubelt.util_hash module
• ubelt.util_import module
• ubelt.util_indexable module
• ubelt.util_io module
• ubelt.util_links module
• ubelt.util_list module
• ubelt.util_memoize module
• ubelt.util_mixins module
• ubelt.util_path module
• ubelt.util_platform module
• ubelt.util_str module
• ubelt.util_stream module
• ubelt.util_time module

Module contents

UBelt is a “utility belt” of commonly needed utility and helper functions. It is a currated collection of top-level utilities with functionality that falls into a mixture of categories.

The source code is available at https://github.com/Erotemic/ubelt. We also have Jupyter notebook demos.

The ubelt API is organized by submodules containing related functionality. Each submodule contains top level overview documentation, and each function contains a docstring with at least one example.

NOTE: The README on github contains information and examples complementary to these docs.

class ubelt.AutoDict

Bases: dict

An infinitely nested default dict of dicts.

Implementation of Perl’s autovivification feature.

SeeAlso:

AutoOrderedDict - the ordered version

References

SO_651794

http://stackoverflow.com/questions/651794/init-dict-of-dicts

Example

>>> import ubelt as ub
>>> auto = ub.AutoDict()
>>> auto[0][10][100] = None
>>> assert str(auto) == '{0: {10: {100: None}}}'

to_dict()

Recursively casts a AutoDict into a regular dictionary. All nested AutoDict values are also converted.

Returns

a copy of this dict without autovivification

Return type

dict

Example

>>> from ubelt.util_dict import AutoDict
>>> auto = AutoDict()
>>> auto[1] = 1
>>> auto['n1'] = AutoDict()
>>> static = auto.to_dict()
>>> assert not isinstance(static, AutoDict)
>>> assert not isinstance(static['n1'], AutoDict)

class ubelt.AutoOrderedDict

Bases: collections.OrderedDict, ubelt.util_dict.AutoDict

An infinitely nested default dict of dicts that maintains the ordering of items.

SeeAlso:

AutoDict - the unordered version of this class

Example

>>> import ubelt as ub
>>> auto = ub.AutoOrderedDict()
>>> auto[0][3] = 3
>>> auto[0][2] = 2
>>> auto[0][1] = 1
>>> assert list(auto[0].values()) == [3, 2, 1]

class ubelt.CacheStamp(fname, dpath, cfgstr=None, product=None, hasher='sha1', verbose=None, enabled=True, depends=None, meta=None)

Bases: object

Quickly determine if a file-producing computation has been done.

Writes a file that marks that a procedure has been done by writing a “stamp” file to disk. Removing the stamp file will force recomputation. However, removing or changing the result of the computation may not trigger recomputation unless specific handling is done or the expected “product” of the computation is a file and registered with the stamper. If hasher is None, we only check if the product exists, and we ignore its hash, otherwise it checks that the hash of the product is the same.

Parameters

• fname (str) – Name of the stamp file

• dpath (str | PathLike | None) – Where to store the cached stamp file

• product (str | PathLike | Sequence[str | PathLike] | None) – Path or paths that we expect the computation to produce. If specified the hash of the paths are stored.

• hasher (str, default=’sha1’) – The type of hasher used to compute the file hash of product. If None, then we assume the file has not been corrupted or changed. Defaults to sha1.

• verbose (bool, default=None) – Passed to internal ub.Cacher object

• enabled (bool, default=True) – if False, expired always returns True

• depends (str | List[str] | None) – Indicate dependencies of this cache. If the dependencies change, then the cache is recomputed. New to CacheStamp in version 0.9.2, replaces cfgstr.

• meta (object | None) – Metadata that is also saved with the cfgstr. This can be useful to indicate how the cfgstr was constructed. New to CacheStamp in version 0.9.2.

• cfgstr (str | None) – DEPRECATED in favor or depends. Configuration associated with the stamped computation. A common pattern is to call ubelt.hash_data() on a dependency list.

  Deprecated in favor of depends. Indicates the state. Either this string or a hash of this string will be used to identify the cache. A cfgstr should always be reasonably readable, thus it is good practice to hash extremely detailed cfgstrs to a reasonable readable level. Use meta to store make original details persist.

Todo

• [ ] expiration time delta or date time (also remember when renewed)

Example

>>> import ubelt as ub
>>> from os.path import join
>>> # Stamp the computation of expensive-to-compute.txt
>>> dpath = ub.ensure_app_cache_dir('ubelt', 'test-cache-stamp')
>>> ub.delete(dpath)
>>> ub.ensuredir(dpath)
>>> product = join(dpath, 'expensive-to-compute.txt')
>>> self = CacheStamp('somedata', depends='someconfig', dpath=dpath,
>>>                   product=product, hasher=None)
>>> self.hasher = None
>>> if self.expired():
>>>     ub.writeto(product, 'very expensive')
>>>     self.renew()
>>> assert not self.expired()
>>> # corrupting the output will not expire in non-robust mode
>>> ub.writeto(product, 'corrupted')
>>> assert not self.expired()
>>> self.hasher = 'sha1'
>>> # but it will expire if we are in robust mode
>>> assert self.expired()
>>> # deleting the product will cause expiration in any mode
>>> self.hasher = None
>>> ub.delete(product)
>>> assert self.expired()

expired(cfgstr=None, product=None)

Check to see if a previously existing stamp is still valid and if the expected result of that computation still exists.

Parameters

• cfgstr (str | None) – overrides the instance-level cfgstr

• product (str | PathLike | Sequence[str | PathLike] | None) – override the default product if specified

Returns

True if the stamp is invalid or does not exist.

Return type

bool

renew(cfgstr=None, product=None)

Recertify that the product has been recomputed by writing a new certificate to disk.

Returns

certificate information

Return type

dict

class ubelt.Cacher(fname, depends=None, dpath=None, appname='ubelt', ext='.pkl', meta=None, verbose=None, enabled=True, log=None, hasher='sha1', protocol=- 1, cfgstr=None)

Bases: object

Cacher designed to be quickly integrated into existing scripts.

A dependency string can be specified, which will invalidate the cache if it changes to an unseen value. The location

Parameters

• fname (str) – A file name. This is the prefix that will be used by the cache. It will always be used as-is.

• depends (str | List[str] | None) – Indicate dependencies of this cache. If the dependencies change, then the cache is recomputed. New in version 0.8.9, replaces cfgstr.

• dpath (str | PathLike | None) – Specifies where to save the cache. If unspecified, Cacher defaults to an application resource dir as given by appname.

• appname (str, default=’ubelt’) – Application name Specifies a folder in the application resource directory where to cache the data if dpath is not specified.

• ext (str, default=’.pkl’) – File extension for the cache format

• meta (object | None) – Metadata that is also saved with the cfgstr. This can be useful to indicate how the cfgstr was constructed.

• verbose (int, default=1) – Level of verbosity. Can be 1, 2 or 3.

• enabled (bool, default=True) – If set to False, then the load and save methods will do nothing.

• log (Callable[[str], Any]) – Overloads the print function. Useful for sending output to loggers (e.g. logging.info, tqdm.tqdm.write, …)

• hasher (str, default=’sha1’) – Type of hashing algorithm to use if cfgstr needs to be condensed to less than 49 characters.

• protocol (int, default=-1) – Protocol version used by pickle. Defaults to the -1 which is the latest protocol. If python 2 compatibility is not required, set to 2.

• cfgstr (str | None) – Deprecated in favor of depends. Indicates the state. Either this string or a hash of this string will be used to identify the cache. A cfgstr should always be reasonably readable, thus it is good practice to hash extremely detailed cfgstrs to a reasonable readable level. Use meta to store make original details persist.

Example

>>> import ubelt as ub
>>> depends = 'repr-of-params-that-uniquely-determine-the-process'
>>> # Create a cacher and try loading the data
>>> cacher = ub.Cacher('demo_process', depends, verbose=4)
>>> cacher.clear()
>>> data = cacher.tryload()
>>> if data is None:
>>>     # Put expensive functions in if block when cacher misses
>>>     myvar1 = 'result of expensive process'
>>>     myvar2 = 'another result'
>>>     # Tell the cacher to write at the end of the if block
>>>     # It is idomatic to put results in an object named data
>>>     data = myvar1, myvar2
>>>     cacher.save(data)
>>> # Last part of the Cacher pattern is to unpack the data object
>>> myvar1, myvar2 = data
>>> #
>>> # If we know the data exists, we can also simply call load
>>> data = cacher.tryload()

Example

>>> # The previous example can be shorted if only a single value
>>> from ubelt.util_cache import Cacher
>>> depends = 'repr-of-params-that-uniquely-determine-the-process'
>>> # Create a cacher and try loading the data
>>> cacher = Cacher('demo_process', depends)
>>> myvar = cacher.tryload()
>>> if myvar is None:
>>>     myvar = ('result of expensive process', 'another result')
>>>     cacher.save(myvar)
>>> assert cacher.exists(), 'should now exist'

VERBOSE = 1

FORCE_DISABLE = False

get_fpath(cfgstr=None)

Reports the filepath that the cacher will use.

It will attempt to use ‘{fname}_{cfgstr}{ext}’ unless that is too long. Then cfgstr will be hashed.

Parameters

cfgstr (str | None) – overrides the instance-level cfgstr

Returns

str | PathLike

Example

>>> # xdoctest: +REQUIRES(module:pytest)
>>> from ubelt.util_cache import Cacher
>>> import pytest
>>> with pytest.warns(UserWarning):
>>>     cacher = Cacher('test_cacher1')
>>>     cacher.get_fpath()
>>> self = Cacher('test_cacher2', depends='cfg1')
>>> self.get_fpath()
>>> self = Cacher('test_cacher3', depends='cfg1' * 32)
>>> self.get_fpath()

exists(cfgstr=None)

Check to see if the cache exists

Parameters

cfgstr (str | None) – overrides the instance-level cfgstr

Returns

bool

existing_versions()

Returns data with different cfgstr values that were previously computed with this cacher.

Yields

str – paths to cached files corresponding to this cacher

Example

>>> from ubelt.util_cache import Cacher
>>> # Ensure that some data exists
>>> known_fpaths = set()
>>> import ubelt as ub
>>> dpath = ub.ensure_app_cache_dir('ubelt',
>>>                                 'test-existing-versions')
>>> ub.delete(dpath)  # start fresh
>>> cacher = Cacher('versioned_data_v2', depends='1', dpath=dpath)
>>> cacher.ensure(lambda: 'data1')
>>> known_fpaths.add(cacher.get_fpath())
>>> cacher = Cacher('versioned_data_v2', depends='2', dpath=dpath)
>>> cacher.ensure(lambda: 'data2')
>>> known_fpaths.add(cacher.get_fpath())
>>> # List previously computed configs for this type
>>> from os.path import basename
>>> cacher = Cacher('versioned_data_v2', depends='2', dpath=dpath)
>>> exist_fpaths = set(cacher.existing_versions())
>>> exist_fnames = list(map(basename, exist_fpaths))
>>> print('exist_fnames = {!r}'.format(exist_fnames))
>>> assert exist_fpaths.issubset(known_fpaths)

clear(cfgstr=None)

Removes the saved cache and metadata from disk

Parameters

cfgstr (str | None) – overrides the instance-level cfgstr

tryload(cfgstr=None, on_error='raise')

Like load, but returns None if the load fails due to a cache miss.

Parameters

• cfgstr (str | None) – overrides the instance-level cfgstr

• on_error (str, default=’raise’) – How to handle non-io errors errors. Either ‘raise’, which re-raises the exception, or ‘clear’ which deletes the cache and returns None.

Returns

the cached data if it exists, otherwise returns None

Return type

None | object

load(cfgstr=None)

Load the data cached and raise an error if something goes wrong.

Parameters

cfgstr (str | None) – overrides the instance-level cfgstr

Returns

the cached data

Return type

object

Raises

IOError - if the data is unable to be loaded. This could be due to – a cache miss or because the cache is disabled.

Example

>>> from ubelt.util_cache import *  # NOQA
>>> # Setting the cacher as enabled=False turns it off
>>> cacher = Cacher('test_disabled_load', '', enabled=True)
>>> cacher.save('data')
>>> assert cacher.load() == 'data'
>>> cacher.enabled = False
>>> assert cacher.tryload() is None

save(data, cfgstr=None)

Writes data to path specified by self.fpath(cfgstr).

Metadata containing information about the cache will also be appended to an adjacent file with the .meta suffix.

Parameters

• data (object) – arbitrary pickleable object to be cached

• cfgstr (str | None) – overrides the instance-level cfgstr

Example

>>> from ubelt.util_cache import *  # NOQA
>>> # Normal functioning
>>> depends = 'long-cfg' * 32
>>> cacher = Cacher('test_enabled_save', depends=depends)
>>> cacher.save('data')
>>> assert exists(cacher.get_fpath()), 'should be enabled'
>>> assert exists(cacher.get_fpath() + '.meta'), 'missing metadata'
>>> # Setting the cacher as enabled=False turns it off
>>> cacher2 = Cacher('test_disabled_save', 'params', enabled=False)
>>> cacher2.save('data')
>>> assert not exists(cacher2.get_fpath()), 'should be disabled'

ensure(func, *args, **kwargs)

Wraps around a function. A cfgstr must be stored in the base cacher.

Parameters

• func (Callable) – function that will compute data on cache miss

• *args – passed to func

• **kwargs – passed to func

Example

>>> from ubelt.util_cache import *  # NOQA
>>> def func():
>>>     return 'expensive result'
>>> fname = 'test_cacher_ensure'
>>> depends = 'func params'
>>> cacher = Cacher(fname, depends=depends)
>>> cacher.clear()
>>> data1 = cacher.ensure(func)
>>> data2 = cacher.ensure(func)
>>> assert data1 == 'expensive result'
>>> assert data1 == data2
>>> cacher.clear()

class ubelt.CaptureStdout(suppress=True, enabled=True, **kwargs)

Bases: ubelt.util_stream.CaptureStream

Context manager that captures stdout and stores it in an internal stream

Parameters

• suppress (bool, default=True) – if True, stdout is not printed while captured

• enabled (bool, default=True) – does nothing if this is False

• **kwargs – used for backwards compatibility with misspelled deprecated params.

Example

>>> import ubelt as ub
>>> self = ub.CaptureStdout(suppress=True)
>>> print('dont capture the table flip (╯°□°）╯︵ ┻━┻')
>>> with self:
...     text = 'capture the heart ♥'
...     print(text)
>>> print('dont capture look of disapproval ಠ_ಠ')
>>> import six
>>> assert isinstance(self.text, six.text_type)
>>> assert self.text == text + '\n', 'failed capture text'

Example

>>> import ubelt as ub
>>> self = ub.CaptureStdout(suppress=False)
>>> with self:
...     print('I am captured and printed in stdout')
>>> assert self.text.strip() == 'I am captured and printed in stdout'

Example

>>> import ubelt as ub
>>> self = ub.CaptureStdout(suppress=True, enabled=False)
>>> with self:
...     print('dont capture')
>>> assert self.text is None

log_part()

Log what has been captured so far

start()

stop()

Example

>>> import ubelt as ub
>>> ub.CaptureStdout(enabled=False).stop()
>>> ub.CaptureStdout(enabled=True).stop()

close()

class ubelt.CaptureStream

Bases: object

Generic class for capturing streaming output from stdout or stderr

class ubelt.DownloadManager(download_root=None, mode='thread', max_workers=None, cache=True)

Bases: object

Simple implementation of the download manager

Variables

• download_root (str | PathLike) – default download location

• jobs (List[concurrent.futures.Future]) – list of jobs

Example

>>> # xdoctest: +REQUIRES(--network)
>>> import ubelt as ub
>>> # Download a file with a known hash
>>> manager = ub.DownloadManager()
>>> job = manager.submit(
>>>     'http://i.imgur.com/rqwaDag.png',
>>>     hash_prefix='31a129618c87dd667103e7154182e3c39a605eefe90f84f2283f3c87efee8e40'
>>> )
>>> fpath = job.result()
>>> print('fpath = {!r}'.format(fpath))

Example

>>> # Does not require network
>>> import ubelt as ub
>>> manager = ub.DownloadManager()
>>> for i in range(1000):
...     job = manager.submit('localhost/might-not-exist-i-{}'.format(i))
>>> file_paths = []
>>> for job in manager.as_completed(prog=True):
...     try:
...         fpath = job.result()
...         file_paths += [fpath]
...     except Exception:
...         pass
>>> print('file_paths = {!r}'.format(file_paths))

Example

>>> # xdoctest: +REQUIRES(--network)
>>> import pytest
>>> import ubelt as ub
>>> manager = ub.DownloadManager()
>>> item1 = {
>>>     'url': 'https://data.kitware.com/api/v1/item/5b4039308d777f2e6225994c/download',
>>>     'dst': 'forgot_what_the_name_really_is',
>>>     'hash_prefix': 'c98a46cb31205cf',
>>>     'hasher': 'sha512',
>>> }
>>> item2 = {
>>>     'url': 'http://i.imgur.com/rqwaDag.png',
>>>     'hash_prefix': 'f79ea24571da6ddd2ba12e3d57b515249ecb8a35',
>>>     'hasher': 'sha1',
>>> }
>>> item1 = item2  # hack around SSL error
>>> manager.submit(**item1)
>>> manager.submit(**item2)
>>> for job in manager.as_completed(prog=True, verbose=3):
>>>     fpath = job.result()
>>>     print('fpath = {!r}'.format(fpath))

submit(url, dst=None, hash_prefix=None, hasher='sha256')

Add a job to the download Queue

Parameters

• url (str | PathLike) – pointer to the data to download

• dst (str | None) – The relative or absolute path to download to. If unspecified, the destination name is derived from the url.

• hash_prefix (str | None) – If specified, verifies that the hash of the downloaded file starts with this.

• hasher (str, default=’sha256’) – hashing algorithm to use if hash_prefix is specified.

Returns

a Future object that will point to the downloaded location.

Return type

concurrent.futures.Future

as_completed(prog=None, desc=None, verbose=1)

Generate completed jobs as they become available

Example

>>> import pytest
>>> import ubelt as ub
>>> download_root = ub.ensure_app_config_dir('ubelt', 'dlman')
>>> manager = ub.DownloadManager(download_root=download_root,
>>>                              cache=False)
>>> for i in range(3):
>>>     manager.submit('localhost')
>>> results = list(manager)
>>> print('results = {!r}'.format(results))
>>> manager.shutdown()

shutdown()

Cancel all jobs and close all connections.

class ubelt.Executor(mode='thread', max_workers=0)

Bases: object

Wrapper around a specific executor.

Abstracts Serial, Thread, and Process Executor via arguments.

Parameters

• mode (str, default=’thread’) – either thread, serial, or process

• max_workers (int, default=0) – number of workers. If 0, serial is forced.

Example

>>> import platform
>>> import sys
>>> # The process backend breaks pyp3 when using coverage
>>> if 'pypy' in platform.python_implementation().lower():
...     import pytest
...     pytest.skip('not testing process on pypy')
>>> if sys.platform.startswith('win32'):
...     import pytest
...     pytest.skip('not running this test on win32 for now')
>>> import ubelt as ub
>>> # Fork before threading!
>>> # https://pybay.com/site_media/slides/raymond2017-keynote/combo.html
>>> self1 = ub.Executor(mode='serial', max_workers=0)
>>> self1.__enter__()
>>> self2 = ub.Executor(mode='process', max_workers=2)
>>> self2.__enter__()
>>> self3 = ub.Executor(mode='thread', max_workers=2)
>>> self3.__enter__()
>>> jobs = []
>>> jobs.append(self1.submit(sum, [1, 2, 3]))
>>> jobs.append(self1.submit(sum, [1, 2, 3]))
>>> jobs.append(self2.submit(sum, [10, 20, 30]))
>>> jobs.append(self2.submit(sum, [10, 20, 30]))
>>> jobs.append(self3.submit(sum, [4, 5, 5]))
>>> jobs.append(self3.submit(sum, [4, 5, 5]))
>>> for job in jobs:
>>>     result = job.result()
>>>     print('result = {!r}'.format(result))
>>> self1.__exit__(None, None, None)
>>> self2.__exit__(None, None, None)
>>> self3.__exit__(None, None, None)

Example

>>> import ubelt as ub
>>> self1 = ub.Executor(mode='serial', max_workers=0)
>>> with self1:
>>>     jobs = []
>>>     for i in range(10):
>>>         jobs.append(self1.submit(sum, [i + 1, i]))
>>>     for job in jobs:
>>>         job.add_done_callback(lambda x: print('done callback got x = {}'.format(x)))
>>>         result = job.result()
>>>         print('result = {!r}'.format(result))

submit(func, *args, **kw)

Calls the submit function of the underlying backend.

Returns

a future representing the job

Return type

concurrent.futures.Future

shutdown()

Calls the shutdown function of the underlying backend.

map(fn, *iterables, **kwargs)

Calls the map function of the underlying backend.

CommandLine

xdoctest -m /home/joncrall/code/ubelt/ubelt/util_futures.py Executor.map

Example

>>> import ubelt as ub
>>> import concurrent.futures
>>> import string
>>> with ub.Executor(mode='serial') as executor:
...     result_iter = executor.map(int, string.digits)
...     results = list(result_iter)
>>> print('results = {!r}'.format(results))
results = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> with ub.Executor(mode='thread', max_workers=2) as executor:
...     result_iter = executor.map(int, string.digits)
...     results = list(result_iter)
>>> # xdoctest: +IGNORE_WANT
>>> print('results = {!r}'.format(results))
results = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

class ubelt.FormatterExtensions

Bases: object

Helper class for managing non-builtin (e.g. numpy) format types.

This module (ubelt.util_format) maintains a global set of basic extensions, but it is also possible to create a locally scoped set of extensions and explicitly pass it to repr2. The following example demonstrates this.

Example

>>> import ubelt as ub
>>> class MyObject(object):
>>>     pass
>>> data = {'a': [1, 2.2222, MyObject()], 'b': MyObject()}
>>> # Create a custom set of extensions
>>> extensions = ub.FormatterExtensions()
>>> # Register a function to format your specific type
>>> @extensions.register(MyObject)
>>> def format_myobject(data, **kwargs):
>>>     return 'I can do anything here'
>>> # Repr2 will now respect the passed custom extensions
>>> # Note that the global extensions will still be respected
>>> # unless they are overloaded.
>>> print(ub.repr2(data, nl=-1, precision=1, extensions=extensions))
{
    'a': [1, 2.2, I can do anything here],
    'b': I can do anything here
}
>>> # Overload the formatter for float and int
>>> @extensions.register((float, int))
>>> def format_myobject(data, **kwargs):
>>>     return str((data + 10) // 2)
>>> print(ub.repr2(data, nl=-1, precision=1, extensions=extensions))
{
    'a': [5, 6.0, I can do anything here],
    'b': I can do anything here
}

register(key)

Registers a custom formatting function with ub.repr2

Parameters

key (Type | Tuple[Type] | str) – indicator of the type

Returns

decorator function

Return type

Callable

lookup(data)

Returns an appropriate function to format data if one has been registered.

class ubelt.IndexableWalker(data, dict_cls=(<class 'dict'>, ), list_cls=(<class 'list'>, <class 'tuple'>))

Bases: collections.abc.Generator

Traverses through a nested tree-liked indexable structure.

Generates a path and value to each node in the structure. The path is a list of indexes which if applied in order will reach the value.

The __setitem__ method can be used to modify a nested value based on the path returned by the generator.

When generating values, you can use “send” to prevent traversal of a particular branch.

RelatedWork:

• https://pypi.org/project/python-benedict/ - implements a dictionary

  subclass with similar nested indexing abilities.

Example

>>> # Given Nested Data
>>> data = {
>>>     'foo': {'bar': 1},
>>>     'baz': [{'biz': 3}, {'buz': [4, 5, 6]}],
>>> }
>>> # Create an IndexableWalker
>>> walker = IndexableWalker(data)
>>> # We iterate over the data as if it was flat
>>> # ignore the <want> string due to order issues on older Pythons
>>> # xdoctest: +IGNORE_WANT
>>> for path, val in walker:
>>>     print(path)
['foo']
['baz']
['baz', 0]
['baz', 1]
['baz', 1, 'buz']
['baz', 1, 'buz', 0]
['baz', 1, 'buz', 1]
['baz', 1, 'buz', 2]
['baz', 0, 'biz']
['foo', 'bar']
>>> # We can use "paths" as keys to getitem into the walker
>>> path = ['baz', 1, 'buz', 2]
>>> val = walker[path]
>>> assert val == 6
>>> # We can use "paths" as keys to setitem into the walker
>>> assert data['baz'][1]['buz'][2] == 6
>>> walker[path] = 7
>>> assert data['baz'][1]['buz'][2] == 7
>>> # We can use "paths" as keys to delitem into the walker
>>> assert data['baz'][1]['buz'][1] == 5
>>> del walker[['baz', 1, 'buz', 1]]
>>> assert data['baz'][1]['buz'][1] == 7

Example

>>> # Create nested data
>>> # xdoctest: +REQUIRES(module:numpy)
>>> import numpy as np
>>> import ubelt as ub
>>> data = ub.ddict(lambda: int)
>>> data['foo'] = ub.ddict(lambda: int)
>>> data['bar'] = np.array([1, 2, 3])
>>> data['foo']['a'] = 1
>>> data['foo']['b'] = np.array([1, 2, 3])
>>> data['foo']['c'] = [1, 2, 3]
>>> data['baz'] = 3
>>> print('data = {}'.format(ub.repr2(data, nl=True)))
>>> # We can walk through every node in the nested tree
>>> walker = IndexableWalker(data)
>>> for path, value in walker:
>>>     print('walk path = {}'.format(ub.repr2(path, nl=0)))
>>>     if path[-1] == 'c':
>>>         # Use send to prevent traversing this branch
>>>         got = walker.send(False)
>>>         # We can modify the value based on the returned path
>>>         walker[path] = 'changed the value of c'
>>> print('data = {}'.format(ub.repr2(data, nl=True)))
>>> assert data['foo']['c'] == 'changed the value of c'

Example

>>> # Test sending false for every data item
>>> # xdoctest: +REQUIRES(module:numpy)
>>> import ubelt as ub
>>> import numpy as np
>>> data = {1: 1}
>>> walker = IndexableWalker(data)
>>> for path, value in walker:
>>>     print('walk path = {}'.format(ub.repr2(path, nl=0)))
>>>     walker.send(False)
>>> data = {}
>>> walker = IndexableWalker(data)
>>> for path, value in walker:
>>>     walker.send(False)

next()

send(arg) → send 'arg' into generator,

return next yielded value or raise StopIteration.

throw(typ[, val[, tb]]) → raise exception in generator,

return next yielded value or raise StopIteration.

class ubelt.JobPool(mode='thread', max_workers=0)

Bases: object

Abstracts away boilerplate of submitting and collecting jobs

This is a basic wrapper around ubelt.util_futures.Executor that simplifies the most basic case.

Example

>>> import ubelt as ub
>>> def worker(data):
>>>     return data + 1
>>> pool = ub.JobPool('thread', max_workers=16)
>>> for data in ub.ProgIter(range(10), desc='submit jobs'):
>>>     pool.submit(worker, data)
>>> final = []
>>> for job in pool.as_completed(desc='collect jobs'):
>>>     info = job.result()
>>>     final.append(info)
>>> print('final = {!r}'.format(final))

submit(func, *args, **kwargs)

Submit a job managed by the pool

Parameters

• func (Callable[…, Any]) – A callable that will take as many arguments as there are passed iterables.

• *args – positional arguments to pass to the function

• *kwargs – keyword arguments to pass to the function

Returns

a future representing the job

Return type

concurrent.futures.Future

shutdown()

as_completed(timeout=None, desc=None, progkw=None)

Generates completed jobs in an arbitrary order

Parameters

• timeout (float | None) – Specify the the maximum number of seconds to wait for a job.

• desc (str | None) – if specified, reports progress with a ubelt.progiter.ProgIter object.

• progkw (dict | None) – extra keyword arguments to ubelt.progiter.ProgIter.

Yields

concurrent.futures.Future – The completed future object containing the results of a job.

CommandLine

xdoctest -m ubelt.util_futures JobPool.as_completed

Example

>>> import ubelt as ub
>>> pool = ub.JobPool('thread', max_workers=8)
>>> text = ub.paragraph(
...     '''
...     UDP is a cool protocol, check out the wiki:
...
...     UDP-based Data Transfer Protocol (UDT), is a high-performance
...     data transfer protocol designed for transferring large
...     volumetric datasets over high-speed wide area networks. Such
...     settings are typically disadvantageous for the more common TCP
...     protocol.
...     ''')
>>> for word in text.split(' '):
...     pool.submit(print, word)
>>> for _ in pool.as_completed():
...     pass
>>> pool.shutdown()

class ubelt.NiceRepr

Bases: object

Inherit from this class and define __nice__ to “nicely” print your objects.

Defines __str__ and __repr__ in terms of __nice__ function Classes that inherit from NiceRepr should redefine __nice__. If the inheriting class has a __len__, method then the default __nice__ method will return its length.

Example

>>> import ubelt as ub
>>> class Foo(ub.NiceRepr):
...    def __nice__(self):
...        return 'info'
>>> foo = Foo()
>>> assert str(foo) == '<Foo(info)>'
>>> assert repr(foo).startswith('<Foo(info) at ')

Example

>>> import ubelt as ub
>>> class Bar(ub.NiceRepr):
...    pass
>>> bar = Bar()
>>> import pytest
>>> with pytest.warns(RuntimeWarning) as record:
>>>     assert 'object at' in str(bar)
>>>     assert 'object at' in repr(bar)

Example

>>> import ubelt as ub
>>> class Baz(ub.NiceRepr):
...    def __len__(self):
...        return 5
>>> baz = Baz()
>>> assert str(baz) == '<Baz(5)>'

Example

>>> import ubelt as ub
>>> # If your nice message has a bug, it shouldn't bring down the house
>>> class Foo(ub.NiceRepr):
...    def __nice__(self):
...        assert False
>>> foo = Foo()
>>> import pytest
>>> with pytest.warns(RuntimeWarning) as record:
>>>     print('foo = {!r}'.format(foo))
foo = <...Foo ...>

class ubelt.OrderedSet(iterable=None)

Bases: collections.abc.MutableSet, collections.abc.Sequence

An OrderedSet is a custom MutableSet that remembers its order, so that every entry has an index that can be looked up.

Example

>>> OrderedSet([1, 1, 2, 3, 2])
OrderedSet([1, 2, 3])

copy()

Return a shallow copy of this object.

Example

>>> this = OrderedSet([1, 2, 3])
>>> other = this.copy()
>>> this == other
True
>>> this is other
False

add(key)

Add key as an item to this OrderedSet, then return its index.

If key is already in the OrderedSet, return the index it already had.

Example

>>> oset = OrderedSet()
>>> oset.append(3)
0
>>> print(oset)
OrderedSet([3])

append(key)

Add key as an item to this OrderedSet, then return its index.

If key is already in the OrderedSet, return the index it already had.

Example

>>> oset = OrderedSet()
>>> oset.append(3)
0
>>> print(oset)
OrderedSet([3])

update(sequence)

Update the set with the given iterable sequence, then return the index of the last element inserted.

Example

>>> oset = OrderedSet([1, 2, 3])
>>> oset.update([3, 1, 5, 1, 4])
4
>>> print(oset)
OrderedSet([1, 2, 3, 5, 4])

index(key)

Get the index of a given entry, raising an IndexError if it’s not present.

key can be an iterable of entries that is not a string, in which case this returns a list of indices.

Example

>>> oset = OrderedSet([1, 2, 3])
>>> oset.index(2)
1

get_loc(key)

Get the index of a given entry, raising an IndexError if it’s not present.

key can be an iterable of entries that is not a string, in which case this returns a list of indices.

Example

>>> oset = OrderedSet([1, 2, 3])
>>> oset.index(2)
1

get_indexer(key)

Get the index of a given entry, raising an IndexError if it’s not present.

key can be an iterable of entries that is not a string, in which case this returns a list of indices.

Example

>>> oset = OrderedSet([1, 2, 3])
>>> oset.index(2)
1

pop()

Remove and return the last element from the set.

Raises KeyError if the set is empty.

Example

>>> oset = OrderedSet([1, 2, 3])
>>> oset.pop()
3

discard(key)

Remove an element. Do not raise an exception if absent.

The MutableSet mixin uses this to implement the .remove() method, which does raise an error when asked to remove a non-existent item.

Example

>>> oset = OrderedSet([1, 2, 3])
>>> oset.discard(2)
>>> print(oset)
OrderedSet([1, 3])
>>> oset.discard(2)
>>> print(oset)
OrderedSet([1, 3])

clear()

Remove all items from this OrderedSet.

union(*sets)

Combines all unique items. Each items order is defined by its first appearance.

Example

>>> oset = OrderedSet.union(OrderedSet([3, 1, 4, 1, 5]), [1, 3], [2, 0])
>>> print(oset)
OrderedSet([3, 1, 4, 5, 2, 0])
>>> oset.union([8, 9])
OrderedSet([3, 1, 4, 5, 2, 0, 8, 9])
>>> oset | {10}
OrderedSet([3, 1, 4, 5, 2, 0, 10])

intersection(*sets)

Returns elements in common between all sets. Order is defined only by the first set.

Example

>>> oset = OrderedSet.intersection(OrderedSet([0, 1, 2, 3]), [1, 2, 3])
>>> print(oset)
OrderedSet([1, 2, 3])
>>> oset.intersection([2, 4, 5], [1, 2, 3, 4])
OrderedSet([2])
>>> oset.intersection()
OrderedSet([1, 2, 3])

difference(*sets)

Returns all elements that are in this set but not the others.

Example

>>> OrderedSet([1, 2, 3]).difference(OrderedSet([2]))
OrderedSet([1, 3])
>>> OrderedSet([1, 2, 3]).difference(OrderedSet([2]), OrderedSet([3]))
OrderedSet([1])
>>> OrderedSet([1, 2, 3]) - OrderedSet([2])
OrderedSet([1, 3])
>>> OrderedSet([1, 2, 3]).difference()
OrderedSet([1, 2, 3])

issubset(other)

Report whether another set contains this set.

Example

>>> OrderedSet([1, 2, 3]).issubset({1, 2})
False
>>> OrderedSet([1, 2, 3]).issubset({1, 2, 3, 4})
True
>>> OrderedSet([1, 2, 3]).issubset({1, 4, 3, 5})
False

issuperset(other)

Report whether this set contains another set.

Example

>>> OrderedSet([1, 2]).issuperset([1, 2, 3])
False
>>> OrderedSet([1, 2, 3, 4]).issuperset({1, 2, 3})
True
>>> OrderedSet([1, 4, 3, 5]).issuperset({1, 2, 3})
False

symmetric_difference(other)

Return the symmetric difference of two OrderedSets as a new set. That is, the new set will contain all elements that are in exactly one of the sets.

Their order will be preserved, with elements from self preceding elements from other.

Example

>>> this = OrderedSet([1, 4, 3, 5, 7])
>>> other = OrderedSet([9, 7, 1, 3, 2])
>>> this.symmetric_difference(other)
OrderedSet([4, 5, 9, 2])

difference_update(*sets)

Update this OrderedSet to remove items from one or more other sets.

Example

>>> this = OrderedSet([1, 2, 3])
>>> this.difference_update(OrderedSet([2, 4]))
>>> print(this)
OrderedSet([1, 3])

>>> this = OrderedSet([1, 2, 3, 4, 5])
>>> this.difference_update(OrderedSet([2, 4]), OrderedSet([1, 4, 6]))
>>> print(this)
OrderedSet([3, 5])

intersection_update(other)

Update this OrderedSet to keep only items in another set, preserving their order in this set.

Example

>>> this = OrderedSet([1, 4, 3, 5, 7])
>>> other = OrderedSet([9, 7, 1, 3, 2])
>>> this.intersection_update(other)
>>> print(this)
OrderedSet([1, 3, 7])

symmetric_difference_update(other)

Update this OrderedSet to remove items from another set, then add items from the other set that were not present in this set.

Example

>>> this = OrderedSet([1, 4, 3, 5, 7])
>>> other = OrderedSet([9, 7, 1, 3, 2])
>>> this.symmetric_difference_update(other)
>>> print(this)
OrderedSet([4, 5, 9, 2])

class ubelt.Path(*args, **kwargs)

Bases: pathlib.PosixPath

An extension of pathlib.Path with extra convenience methods

touch(mode=438, exist_ok=True)

Create this file with the given access mode, if it doesn’t exist.

Returns

returns itself

Return type

Path

Notes

The ubelt.util_io.touch() function currently has a slightly different implementation. This uses whatever the pathlib version is. This may change in the future.

ensuredir(mode=511)

Concise alias of self.mkdir(parents=True, exist_ok=True)

Returns

returns itself

Return type

Path

Example

>>> import ubelt as ub
>>> cache_dpath = ub.ensure_app_cache_dir('ubelt')
>>> dpath = ub.Path(join(cache_dpath, 'ensuredir'))
>>> if dpath.exists():
...     os.rmdir(dpath)
>>> assert not dpath.exists()
>>> dpath.ensuredir()
>>> assert dpath.exists()
>>> dpath.rmdir()

expandvars()

As discussed in [CPythonIssue21301], CPython won’t be adding expandvars to pathlib. I think this is a mistake, so I added it in this extension.

Returns

path with expanded environment variables

Return type

Path

References

CPythonIssue21301

https://bugs.python.org/issue21301

expand()

Expands user tilde and environment variables.

Concise alias of Path(os.path.expandvars(self.expanduser()))

Returns

path with expanded environment variables and tildes

Return type

Path

Example

>>> import ubelt as ub
>>> #home_v1 = ub.Path('$HOME').expand()
>>> home_v2 = ub.Path('~/').expand()
>>> assert isinstance(home_v2, ub.Path)
>>> home_v3 = ub.Path.home()
>>> #print('home_v1 = {!r}'.format(home_v1))
>>> print('home_v2 = {!r}'.format(home_v2))
>>> print('home_v3 = {!r}'.format(home_v3))
>>> assert home_v3 == home_v2 # == home_v1

shrinkuser(home='~')

Inverse of os.path.expanduser().

Parameters

home (str, default=’~’) – symbol used to replace the home path. Defaults to ‘~’, but you might want to use ‘$HOME’ or ‘%USERPROFILE%’ instead.

Returns

path - shortened path replacing the home directory with a symbol

Return type

Path

Example

>>> import ubelt as ub
>>> path = ub.Path('~').expand()
>>> assert str(path.shrinkuser()) == '~'
>>> assert str(ub.Path((str(path) + '1')).shrinkuser()) == str(path) + '1'
>>> assert str((path / '1').shrinkuser()) == join('~', '1')
>>> assert str((path / '1').shrinkuser('$HOME')) == join('$HOME', '1')
>>> assert str(ub.Path('.').shrinkuser()) == '.'

augment(suffix='', prefix='', ext=None, stem=None, dpath=None, relative=None, multidot=False)

Create a new path with a different extension, basename, directory, prefix, and/or suffix.

See augpath() for more details.

Parameters

• suffix (str, default=’’) – placed between the stem and extension

• prefix (str, default=’’) – placed in front of the stem

• ext (str | None, default=None) – if specified, replaces the extension

• stem (str | None, default=None) – if specified, replaces the stem (i.e. basename without extension). Note: named base in augpath().

• dpath (str | PathLike | None, default=None) – if specified, replaces the specified “relative” directory, which by default is the parent directory.

• relative (str | PathLike | None, default=None) – Replaces relative with dpath in path. Has no effect if dpath is not specified. Defaults to the dirname of the input path. experimental not currently implemented.

• multidot (bool, default=False) – Allows extensions to contain multiple dots. Specifically, if False, everything after the last dot in the basename is the extension. If True, everything after the first dot in the basename is the extension.

Returns

augmented path

Return type

Path

Example

>>> import ubelt as ub
>>> path = ub.Path('foo.bar')
>>> suffix = '_suff'
>>> prefix = 'pref_'
>>> ext = '.baz'
>>> newpath = path.augment(suffix, prefix, ext=ext, stem='bar')
>>> print('newpath = {!r}'.format(newpath))
newpath = Path('pref_bar_suff.baz')

delete()

Removes a file or recursively removes a directory. If a path does not exist, then this is does nothing.

SeeAlso:

ubelt.delete()

Returns

reference to self

Return type

Path

Example

>>> import ubelt as ub
>>> from os.path import join
>>> base = ub.Path(ub.ensure_app_cache_dir('ubelt', 'delete_test2'))
>>> dpath1 = (base / 'dir').ensuredir()
>>> (base / 'dir' / 'subdir').ensuredir()
>>> (base / 'dir' / 'to_remove1.txt').touch()
>>> fpath1 = (base / 'dir' / 'subdir' / 'to_remove3.txt').touch()
>>> fpath2 = (base / 'dir' / 'subdir' / 'to_remove2.txt').touch()
>>> assert all(p.exists() for p in [dpath1, fpath1, fpath2])
>>> fpath1.delete()
>>> assert all(p.exists() for p in [dpath1, fpath2])
>>> assert not fpath1.exists()
>>> dpath1.delete()
>>> assert not any(p.exists() for p in [dpath1, fpath1, fpath2])

class ubelt.ProgIter(iterable=None, desc=None, total=None, freq=1, initial=0, eta_window=64, clearline=True, adjust=True, time_thresh=2.0, show_times=True, show_wall=False, enabled=True, verbose=None, stream=None, chunksize=None, rel_adjust_limit=4.0, **kwargs)

Bases: ubelt.progiter._TQDMCompat, ubelt.progiter._BackwardsCompat

Prints progress as an iterator progresses

ProgIter is an alternative to tqdm. ProgIter implements much of the tqdm-API. The main difference between ProgIter and tqdm is that ProgIter does not use threading where as tqdm does.

Variables

• iterable (iterable) – An iterable iterable

• desc (str) – description label to show with progress

• total (int) – Maximum length of the process. If not specified, we estimate it from the iterable, if possible.

• freq (int, default=1) – How many iterations to wait between messages.

• adjust (bool, default=True) – if True freq is adjusted based on time_thresh

• eta_window (int, default=64) – number of previous measurements to use in eta calculation

• clearline (bool, default=True) – if True messages are printed on the same line otherwise each new progress message is printed on new line.

• adjust – if True freq is adjusted based on time_thresh. This may be overwritten depending on the setting of verbose.

• time_thresh (float, default=2.0) – desired amount of time to wait between messages if adjust is True otherwise does nothing

• show_times (bool, default=True) – shows rate and eta

• show_wall (bool, default=False) – show wall time

• initial (int, default=0) – starting index offset

• stream (file, default=sys.stdout) – stream where progress information is written to

• enabled (bool, default=True) – if False nothing happens.

• chunksize (int, optional) – indicates that each iteration processes a batch of this size. Iteration rate is displayed in terms of single-items.

• rel_adjust_limit (float, default=4.0) – Maximum factor update frequency can be adjusted by in a single step.

• verbose (int) – verbosity mode, which controls clearline, adjust, and enabled. The following maps the value of verbose to its effect. 0: enabled=False, 1: enabled=True with clearline=True and adjust=True, 2: enabled=True with clearline=False and adjust=True, 3: enabled=True with clearline=False and adjust=False

Note

Either use ProgIter in a with statement or call prog.end() at the end of the computation if there is a possibility that the entire iterable may not be exhausted.

Note

ProgIter is an alternative to tqdm. The main difference between ProgIter and tqdm is that ProgIter does not use threading where as tqdm does. ProgIter is simpler than tqdm and thus more stable in certain circumstances.

SeeAlso:

tqdm - https://pypi.python.org/pypi/tqdm

References

http://datagenetics.com/blog/february12017/index.html

Example

>>> 
>>> def is_prime(n):
...     return n >= 2 and not any(n % i == 0 for i in range(2, n))
>>> for n in ProgIter(range(100), verbose=1, show_wall=True):
>>>     # do some work
>>>     is_prime(n)
100/100... rate=... Hz, total=..., wall=...

set_extra(extra)

specify a custom info appended to the end of the next message

Todo

• [ ] extra is a bad name; come up with something better and rename

Example

>>> prog = ProgIter(range(100, 300, 100), show_times=False, verbose=3)
>>> for n in prog:
>>>     prog.set_extra('processesing num {}'.format(n))
0/2...
1/2...processesing num 100
2/2...processesing num 200

step(inc=1, force=False)

Manually step progress update, either directly or by an increment.

Parameters

• inc (int, default=1) – number of steps to increment

• force (bool, default=False) – if True forces progress display

Example

>>> n = 3
>>> prog = ProgIter(desc='manual', total=n, verbose=3)
>>> # Need to manually begin and end in this mode
>>> prog.begin()
>>> for _ in range(n):
...     prog.step()
>>> prog.end()

Example

>>> n = 3
>>> # can be used as a context manager in manual mode
>>> with ProgIter(desc='manual', total=n, verbose=3) as prog:
...     for _ in range(n):
...         prog.step()

start()

Alias of ubelt.progiter.ProgIter.begin()

begin()

Initializes information used to measure progress

This only needs to be used if this ProgIter is not wrapping an iterable. Does nothing if the this ProgIter is disabled.

Returns

a chainable self-reference

Return type

ProgIter

end()

Signals that iteration has ended and displays the final message.

This only needs to be used if this ProgIter is not wrapping an iterable. Does nothing if the this ProgIter object is disabled or has already finished.

format_message()

builds a formatted progress message with the current values. This contains the special characters needed to clear lines.

Example

>>> self = ProgIter(clearline=False, show_times=False)
>>> print(repr(self.format_message()))
'    0/?... \n'
>>> self.begin()
>>> self.step()
>>> print(repr(self.format_message()))
' 1/?... \n'

Example

>>> self = ProgIter(chunksize=10, total=100, clearline=False,
>>>                 show_times=False, microseconds=True)
>>> # hack, microseconds=True for coverage, needs real test
>>> print(repr(self.format_message()))
' 0.00% of 10x100... \n'
>>> self.begin()
>>> self.update()  # tqdm alternative to step
>>> print(repr(self.format_message()))
' 1.00% of 10x100... \n'

ensure_newline()

use before any custom printing when using the progress iter to ensure your print statement starts on a new line instead of at the end of a progress line

Example

>>> # Unsafe version may write your message on the wrong line
>>> prog = ProgIter(range(3), show_times=False, freq=2, adjust=False)
>>> for n in prog:
...     print('unsafe message')
 0/3... unsafe message
unsafe message
 2/3... unsafe message
 3/3...
>>> # apparently the safe version does this too.
>>> print('---')
---
>>> prog = ProgIter(range(3), show_times=False, freq=2, adjust=False)
>>> for n in prog:
...     prog.ensure_newline()
...     print('safe message')
 0/3...
safe message
safe message
 2/3...
safe message
 3/3...

display_message()

Writes current progress to the output stream

class ubelt.TeeStringIO(redirect=None)

Bases: _io.StringIO

An IO object that writes to itself and another IO stream.

Variables

redirect (io.IOBase) – The other stream to write to.

Example

>>> import ubelt as ub
>>> redirect = io.StringIO()
>>> self = ub.TeeStringIO(redirect)

isatty()

Returns true of the redirect is a terminal.

Note

Needed for IPython.embed to work properly when this class is used to override stdout / stderr.

fileno()

Returns underlying file descriptor of the redirected IOBase object if one exists.

Example

>>> # Not sure the best way to test, this func is important for
>>> # capturing stdout when ipython embedding
>>> import pytest
>>> with pytest.raises(io.UnsupportedOperation):
>>>     TeeStringIO(redirect=io.StringIO()).fileno()
>>> with pytest.raises(io.UnsupportedOperation):
>>>     TeeStringIO(None).fileno()

property encoding

Gets the encoding of the redirect IO object

Example

>>> import ubelt as ub
>>> redirect = io.StringIO()
>>> assert ub.TeeStringIO(redirect).encoding is None
>>> assert ub.TeeStringIO(None).encoding is None
>>> assert ub.TeeStringIO(sys.stdout).encoding is sys.stdout.encoding
>>> redirect = io.TextIOWrapper(io.StringIO())
>>> assert ub.TeeStringIO(redirect).encoding is redirect.encoding

write(msg)

Write to this and the redirected stream

flush()

Flush to this and the redirected stream

class ubelt.TempDir

Bases: object

Context for creating and cleaning up temporary directories.

Note

This exists because tempfile.TemporaryDirectory was introduced in Python 3.2. Thus once ubelt no longer supports python 2.7, this class will be deprecated.

Example

>>> from ubelt.util_path import *  # NOQA
>>> with TempDir() as self:
>>>     dpath = self.dpath
>>>     assert exists(dpath)
>>> assert not exists(dpath)

Example

>>> from ubelt.util_path import *  # NOQA
>>> self = TempDir()
>>> dpath = self.ensure()
>>> assert exists(dpath)
>>> self.cleanup()
>>> assert not exists(dpath)

ensure()

cleanup()

start()

class ubelt.Timer(label='', verbose=None, newline=True)

Bases: object

Measures time elapsed between a start and end point. Can be used as a with-statement context manager, or using the tic/toc api.

Parameters

• label (str, default=’’) – identifier for printing

• verbose (int, default=None) – verbosity flag, defaults to True if label is given

• newline (bool, default=True) – if False and verbose, print tic and toc on the same line

Variables

• elapsed (float) – number of seconds measured by the context manager

• tstart (float) – time of last tic reported by self._time()

Example

>>> # Create and start the timer using the context manager
>>> import math
>>> timer = Timer('Timer test!', verbose=1)
>>> with timer:
>>>     math.factorial(10)
>>> assert timer.elapsed > 0
tic('Timer test!')
...toc('Timer test!')=...

Example

>>> # Create and start the timer using the tic/toc interface
>>> timer = Timer().tic()
>>> elapsed1 = timer.toc()
>>> elapsed2 = timer.toc()
>>> elapsed3 = timer.toc()
>>> assert elapsed1 <= elapsed2
>>> assert elapsed2 <= elapsed3

tic()

starts the timer

toc()

stops the timer

class ubelt.Timerit(num=1, label=None, bestof=3, unit=None, verbose=None)

Bases: object

Reports the average time to run a block of code.

Unlike %timeit, Timerit can handle multiline blocks of code. It runs inline, and doesn’t depend on magic or strings. Just indent your code and place in a Timerit block. See https://github.com/Erotemic/vimtk for vim functions that will insert one of these in for you (ok that part is a little magic).

Parameters

• num (int, default=1) – number of times to run the loop

• label (str, default=None) – identifier for printing

• bestof (int, default=3) – takes the max over this number of trials

• unit (str) – what units time is reported in

• verbose (int) – verbosity flag, defaults to True if label is given

Variables

• object (measures - labeled measurements taken by this) –

• measurements (rankings - ranked) –

Example

>>> import math
>>> num = 3
>>> t1 = Timerit(num, label='factorial', verbose=1)
>>> for timer in t1:
>>>     # <write untimed setup code here> this example has no setup
>>>     with timer:
>>>         # <write code to time here> for example...
>>>         math.factorial(100)
Timed best=..., mean=... for factorial
>>> # <you can now access Timerit attributes>
>>> assert t1.total_time > 0
>>> assert t1.n_loops == t1.num
>>> assert t1.n_loops == num

Example

>>> # xdoc: +IGNORE_WANT
>>> import math
>>> num = 4
>>> # If the timer object is unused, time will still be recorded,
>>> # but with less precision.
>>> for _ in Timerit(num, 'concise', bestof=2, verbose=2):
>>>     math.factorial(100)
Timed concise for: 4 loops, best of 2
    time per loop: best=1.637 µs, mean=1.935 ± 0.3 µs
>>> # Using the timer object results in the most precise timings
>>> for timer in Timerit(num, 'precise', bestof=2, verbose=3):
>>>     with timer: math.factorial(100)
Timed precise for: 4 loops, best of 2
    body took: 8.696 µs
    time per loop: best=1.754 µs, mean=1.821 ± 0.1 µs

reset(label=None, measures=False)

clears all measurements, allowing the object to be reused

Parameters

• label (str | None) – change the label if specified

• measures (bool, default=False) – if True reset measures

Example

>>> import math
>>> ti = Timerit(num=10, unit='us', verbose=True)
>>> _ = ti.reset(label='10!').call(math.factorial, 10)
Timed best=...s, mean=...s for 10!
>>> _ = ti.reset(label='20!').call(math.factorial, 20)
Timed best=...s, mean=...s for 20!
>>> _ = ti.reset().call(math.factorial, 20)
Timed best=...s, mean=...s for 20!
>>> _ = ti.reset(measures=True).call(math.factorial, 20)

call(func, *args, **kwargs)

Alternative way to time a simple function call using condensed syntax.

Returns

self :

Use min, or mean to get a scalar. Use print to output a report to stdout.

Return type

‘Timerit’

Example

>>> import math
>>> time = Timerit(num=10).call(math.factorial, 50).min()
>>> assert time > 0

property rankings

Orders each list of measurements by ascending time

Example

>>> import math
>>> ti = Timerit(num=1)
>>> _ = ti.reset('a').call(math.factorial, 5)
>>> _ = ti.reset('b').call(math.factorial, 10)
>>> _ = ti.reset('c').call(math.factorial, 20)
>>> ti.rankings
>>> ti.consistency

property consistency

” Take the hamming distance between the preference profiles to as a measure of consistency.

min()

The best time overall.

This is typically the best metric to consider when evaluating the execution time of a function. To understand why consider this quote from the docs of the original timeit module:

‘’’ In a typical case, the lowest value gives a lower bound for how fast your machine can run the given code snippet; higher values in the result vector are typically not caused by variability in Python’s speed, but by other processes interfering with your timing accuracy. So the min() of the result is probably the only number you should be interested in. ‘’’

Returns

minimum measured seconds over all trials

Return type

float

Example

>>> import math
>>> self = Timerit(num=10, verbose=0)
>>> self.call(math.factorial, 50)
>>> assert self.min() > 0

mean()

The mean of the best results of each trial.

Returns

mean of measured seconds

Return type

float

Note

This is typically less informative than simply looking at the min. It is recommended to use min as the expectation value rather than mean in most cases.

Example

>>> import math
>>> self = Timerit(num=10, verbose=0)
>>> self.call(math.factorial, 50)
>>> assert self.mean() > 0

std()

The standard deviation of the best results of each trial.

Returns

standard deviation of measured seconds

Return type

float

Note

As mentioned in the timeit source code, the standard deviation is not often useful. Typically the minimum value is most informative.

Example

>>> import math
>>> self = Timerit(num=10, verbose=1)
>>> self.call(math.factorial, 50)
>>> assert self.std() >= 0

report(verbose=1)

Creates a human readable report

Parameters

verbose (int) – verbosity level. Either 1, 2, or 3.

Returns

the report

Return type

str

SeeAlso:

Timerit.print()

Example

>>> import math
>>> ti = Timerit(num=1).call(math.factorial, 5)
>>> print(ti.report(verbose=1))
Timed best=...s, mean=...s

print(verbose=1)

Prints human readable report using the print function

Parameters

verbose (int) – verbosity level

SeeAlso:

Timerit.report()

Example

>>> import math
>>> Timerit(num=10).call(math.factorial, 50).print(verbose=1)
Timed best=...s, mean=...s
>>> Timerit(num=10).call(math.factorial, 50).print(verbose=2)
Timed for: 10 loops, best of 3
    time per loop: best=...s, mean=...s
>>> Timerit(num=10).call(math.factorial, 50).print(verbose=3)
Timed for: 10 loops, best of 3
    body took: ...
    time per loop: best=...s, mean=...s

ubelt.allsame(iterable, eq=<built-in function eq>)

Determine if all items in a sequence are the same

Parameters

• iterable (Iterable[T]) – items to determine if they are all the same

• eq (Callable[[T, T], bool], default=operator.eq) – function used to test for equality

Returns

True if all items are equal, otherwise False

Return type

bool

Notes

Similar to more_itertools.all_equal()

Example

>>> import ubelt as ub
>>> ub.allsame([1, 1, 1, 1])
True
>>> ub.allsame([])
True
>>> ub.allsame([0, 1])
False
>>> iterable = iter([0, 1, 1, 1])
>>> next(iterable)
>>> ub.allsame(iterable)
True
>>> ub.allsame(range(10))
False
>>> ub.allsame(range(10), lambda a, b: True)
True

ubelt.argflag(key, argv=None)

Determines if a key is specified on the command line.

This is a functional alternative to key in sys.argv.

Parameters

• key (str | Tuple[str, …]) – string or tuple of strings. Each key should be prefixed with two hyphens (i.e. --).

• argv (List[str], default=None) – overrides sys.argv if specified

Returns

flag - True if the key (or any of the keys) was specified

Return type

bool

Example

>>> import ubelt as ub
>>> argv = ['--spam', '--eggs', 'foo']
>>> assert ub.argflag('--eggs', argv=argv) is True
>>> assert ub.argflag('--ans', argv=argv) is False
>>> assert ub.argflag('foo', argv=argv) is True
>>> assert ub.argflag(('bar', '--spam'), argv=argv) is True

ubelt.argmax(indexable, key=None)

Returns index / key of the item with the largest value.

This is similar to numpy.argmax(), but it is written in pure python and works on both lists and dictionaries.

Parameters

• indexable (Iterable[VT] | Mapping[KT, VT]) – indexable to sort by

• key (Callable[[VT], Any], default=None) – customizes the ordering of the indexable

Returns

the index of the item with the maximum value.

Return type

int | KT

Example

>>> import ubelt as ub
>>> assert ub.argmax({'a': 3, 'b': 2, 'c': 100}) == 'c'
>>> assert ub.argmax(['a', 'c', 'b', 'z', 'f']) == 3
>>> assert ub.argmax([[0, 1], [2, 3, 4], [5]], key=len) == 1
>>> assert ub.argmax({'a': 3, 'b': 2, 3: 100, 4: 4}) == 3
>>> assert ub.argmax(iter(['a', 'c', 'b', 'z', 'f'])) == 3

ubelt.argmin(indexable, key=None)

Returns index / key of the item with the smallest value.

This is similar to numpy.argmin(), but it is written in pure python and works on both lists and dictionaries.

Parameters

• indexable (Iterable[VT] | Mapping[KT, VT]) – indexable to sort by

• key (Callable[[VT], VT], default=None) – customizes the ordering of the indexable

Returns

the index of the item with the minimum value.

Return type

int | KT

Example

>>> import ubelt as ub
>>> assert ub.argmin({'a': 3, 'b': 2, 'c': 100}) == 'b'
>>> assert ub.argmin(['a', 'c', 'b', 'z', 'f']) == 0
>>> assert ub.argmin([[0, 1], [2, 3, 4], [5]], key=len) == 2
>>> assert ub.argmin({'a': 3, 'b': 2, 3: 100, 4: 4}) == 'b'
>>> assert ub.argmin(iter(['a', 'c', 'A', 'z', 'f'])) == 2

ubelt.argsort(indexable, key=None, reverse=False)

Returns the indices that would sort a indexable object.

This is similar to numpy.argsort(), but it is written in pure python and works on both lists and dictionaries.

Parameters

• indexable (Iterable[VT] | Mapping[KT, VT]) – indexable to sort by

• key (Callable[[VT], VT] | None, default=None) – customizes the ordering of the indexable

• reverse (bool, default=False) – if True returns in descending order

Returns

indices - list of indices that sorts the indexable

Return type

List[int] | List[KT]

Example

>>> import ubelt as ub
>>> # argsort works on dicts by returning keys
>>> dict_ = {'a': 3, 'b': 2, 'c': 100}
>>> indices = ub.argsort(dict_)
>>> assert list(ub.take(dict_, indices)) == sorted(dict_.values())
>>> # argsort works on lists by returning indices
>>> indexable = [100, 2, 432, 10]
>>> indices = ub.argsort(indexable)
>>> assert list(ub.take(indexable, indices)) == sorted(indexable)
>>> # Can use iterators, but be careful. It exhausts them.
>>> indexable = reversed(range(100))
>>> indices = ub.argsort(indexable)
>>> assert indices[0] == 99
>>> # Can use key just like sorted
>>> indexable = [[0, 1, 2], [3, 4], [5]]
>>> indices = ub.argsort(indexable, key=len)
>>> assert indices == [2, 1, 0]
>>> # Can use reverse just like sorted
>>> indexable = [0, 2, 1]
>>> indices = ub.argsort(indexable, reverse=True)
>>> assert indices == [1, 2, 0]

ubelt.argunique(items, key=None)

Returns indices corresponding to the first instance of each unique item.

Parameters

• items (Sequence[VT]) – indexable collection of items

• key (Callable[[VT], Any], default=None) – custom normalization function. If specified returns items where key(item) is unique.

Returns

indices of the unique items

Return type

Iterator[int]

Example

>>> import ubelt as ub
>>> items = [0, 2, 5, 1, 1, 0, 2, 4]
>>> indices = list(ub.argunique(items))
>>> assert indices == [0, 1, 2, 3, 7]
>>> indices = list(ub.argunique(items, key=lambda x: x % 2 == 0))
>>> assert indices == [0, 2]

ubelt.argval(key, default=NoParam, argv=None)

Get the value of a keyword argument specified on the command line.

Values can be specified as <key> <value> or <key>=<value>

Parameters

• key (str | Tuple[str, …]) – string or tuple of strings. Each key should be prefixed with two hyphens (i.e. --)

• default (T | util_const._NoParamType, default=NoParam) – a value to return if not specified.

• argv (Optional[List[str]], default=None) – uses sys.argv if unspecified

Returns

value - the value specified after the key. It they key is specified multiple times, then the first value is returned.

Return type

str | T

Todo

• [ ] Can we handle the case where the value is a list of long paths?

• [ ] Should we default the first or last specified instance of the flag.

Example

>>> import ubelt as ub
>>> argv = ['--ans', '42', '--quest=the grail', '--ans=6', '--bad']
>>> assert ub.argval('--spam', argv=argv) == ub.NoParam
>>> assert ub.argval('--quest', argv=argv) == 'the grail'
>>> assert ub.argval('--ans', argv=argv) == '42'
>>> assert ub.argval('--bad', argv=argv) == ub.NoParam
>>> assert ub.argval(('--bad', '--bar'), argv=argv) == ub.NoParam

Example

>>> # Test fix for GH Issue #41
>>> import ubelt as ub
>>> argv = ['--path=/path/with/k=3']
>>> ub.argval('--path', argv=argv) == '/path/with/k=3'

ubelt.augpath(path, suffix='', prefix='', ext=None, base=None, dpath=None, relative=None, multidot=False)

Create a new path with a different extension, basename, directory, prefix, and/or suffix.

A prefix is inserted before the basename. A suffix is inserted between the basename and the extension. The basename and extension can be replaced with a new one. Essentially a path is broken down into components (dpath, base, ext), and then recombined as (dpath, prefix, base, suffix, ext) after replacing any specified component.

Parameters

• path (str | PathLike) – a path to augment

• suffix (str, default=’’) – placed between the basename and extension

• prefix (str, default=’’) – placed in front of the basename

• ext (str | None, default=None) – if specified, replaces the extension

• base (str | None, default=None) – if specified, replaces the basename without extension. Note: this is referred to as stem in ub.Path.

• dpath (str | PathLike | None, default=None) – if specified, replaces the specified “relative” directory, which by default is the parent directory.

• relative (str | PathLike | None, default=None) – Replaces relative with dpath in path. Has no effect if dpath is not specified. Defaults to the dirname of the input path. experimental not currently implemented.

• multidot (bool, default=False) – Allows extensions to contain multiple dots. Specifically, if False, everything after the last dot in the basename is the extension. If True, everything after the first dot in the basename is the extension.

Returns

augmented path

Return type

str

Example

>>> import ubelt as ub
>>> path = 'foo.bar'
>>> suffix = '_suff'
>>> prefix = 'pref_'
>>> ext = '.baz'
>>> newpath = ub.augpath(path, suffix, prefix, ext=ext, base='bar')
>>> print('newpath = %s' % (newpath,))
newpath = pref_bar_suff.baz

Example

>>> from ubelt.util_path import *  # NOQA
>>> augpath('foo.bar')
'foo.bar'
>>> augpath('foo.bar', ext='.BAZ')
'foo.BAZ'
>>> augpath('foo.bar', suffix='_')
'foo_.bar'
>>> augpath('foo.bar', prefix='_')
'_foo.bar'
>>> augpath('foo.bar', base='baz')
'baz.bar'
>>> augpath('foo.tar.gz', ext='.zip', multidot=True)
foo.zip
>>> augpath('foo.tar.gz', ext='.zip', multidot=False)
foo.tar.zip
>>> augpath('foo.tar.gz', suffix='_new', multidot=True)
foo_new.tar.gz

ubelt.boolmask(indices, maxval=None)

Constructs a list of booleans where an item is True if its position is in indices otherwise it is False.

Parameters

• indices (List[int]) – list of integer indices

• maxval (int) – length of the returned list. If not specified this is inferred using max(indices)

Returns

mask - a list of booleans. mask[idx] is True if idx in indices

Return type

List[bool]

Note

In the future the arg maxval may change its name to shape

Example

>>> import ubelt as ub
>>> indices = [0, 1, 4]
>>> mask = ub.boolmask(indices, maxval=6)
>>> assert mask == [True, True, False, False, True, False]
>>> mask = ub.boolmask(indices)
>>> assert mask == [True, True, False, False, True]

class ubelt.chunks(items, chunksize=None, nchunks=None, total=None, bordermode='none', legacy=False)

Bases: object

Generates successive n-sized chunks from items.

If the last chunk has less than n elements, bordermode is used to determine fill values.

Parameters

• items (Iterable[T]) – input to iterate over

• chunksize (int) – size of each sublist yielded

• nchunks (int) – number of chunks to create ( cannot be specified if chunksize is specified)

• bordermode (str) – determines how to handle the last case if the length of the input is not divisible by chunksize valid values are: {‘none’, ‘cycle’, ‘replicate’}

• total (int) – hints about the length of the input

Note

FIXME:

When nchunks is given, that’s how many chunks we should get but the issue is that chunksize is not well defined in that instance For instance how do we turn a list with 4 elements into 3 chunks where does the extra item go?

In ubelt <= 0.10.3 there is a bug when specifying nchunks, where it chooses a chunksize that is too large. Specify legacy=True to get the old buggy behavior if needed.

Notes

This is similar to functionality provided by

more_itertools.chunked(), more_itertools.chunked_even(), more_itertools.sliced(), more_itertools.divide(),

Yields

List[T] – subsequent non-overlapping chunks of the input items

References

SO_434287

http://stackoverflow.com/questions/434287/iterate-over-a-list-in-chunks

Example

>>> import ubelt as ub
>>> items = '1234567'
>>> genresult = ub.chunks(items, chunksize=3)
>>> list(genresult)
[['1', '2', '3'], ['4', '5', '6'], ['7']]

Example

>>> import ubelt as ub
>>> items = [1, 2, 3, 4, 5, 6, 7]
>>> genresult = ub.chunks(items, chunksize=3, bordermode='none')
>>> assert list(genresult) == [[1, 2, 3], [4, 5, 6], [7]]
>>> genresult = ub.chunks(items, chunksize=3, bordermode='cycle')
>>> assert list(genresult) == [[1, 2, 3], [4, 5, 6], [7, 1, 2]]
>>> genresult = ub.chunks(items, chunksize=3, bordermode='replicate')
>>> assert list(genresult) == [[1, 2, 3], [4, 5, 6], [7, 7, 7]]

Example

>>> import ubelt as ub
>>> assert len(list(ub.chunks(range(2), nchunks=2))) == 2
>>> assert len(list(ub.chunks(range(3), nchunks=2))) == 2
>>> # Note: ub.chunks will not do the 2,1,1 split
>>> assert len(list(ub.chunks(range(4), nchunks=3))) == 3
>>> assert len(list(ub.chunks([], 2, bordermode='none'))) == 0
>>> assert len(list(ub.chunks([], 2, bordermode='cycle'))) == 0
>>> assert len(list(ub.chunks([], 2, None, bordermode='replicate'))) == 0

Example

>>> from ubelt.util_list import *  # NOQA
>>> def _check_len(self):
...     assert len(self) == len(list(self))
>>> _check_len(chunks(list(range(3)), nchunks=2))
>>> _check_len(chunks(list(range(2)), nchunks=2))
>>> _check_len(chunks(list(range(2)), nchunks=3))

Example

>>> from ubelt.util_list import *  # NOQA
>>> import pytest
>>> assert pytest.raises(ValueError, chunks, range(9))
>>> assert pytest.raises(ValueError, chunks, range(9), chunksize=2, nchunks=2)
>>> assert pytest.raises(TypeError, len, chunks((_ for _ in range(2)), 2))

Example

>>> from ubelt.util_list import *  # NOQA
>>> import ubelt as ub
>>> basis = {
>>>     'legacy': [False, True],
>>>     'chunker': [{'nchunks': 3}, {'nchunks': 4}, {'nchunks': 5}, {'nchunks': 7}, {'chunksize': 3}],
>>>     'items': [range(2), range(4), range(5), range(7), range(9)],
>>>     'bordermode': ['none', 'cycle', 'replicate'],
>>> }
>>> grid_items = list(ub.named_product(basis))
>>> rows = []
>>> for grid_item in ub.ProgIter(grid_items):
>>>     chunker = grid_item.get('chunker')
>>>     grid_item.update(chunker)
>>>     kw = ub.dict_diff(grid_item, {'chunker'})
>>>     self = chunk_iter = ub.chunks(**kw)
>>>     chunked = list(chunk_iter)
>>>     chunk_lens = list(map(len, chunked))
>>>     row = ub.dict_union(grid_item, {'chunk_lens': chunk_lens, 'chunks': chunked})
>>>     row['chunker'] = str(row['chunker'])
>>>     if not row['legacy'] and 'nchunks' in kw:
>>>         assert kw['nchunks'] == row['nchunks']
>>>     row.update(chunk_iter.__dict__)
>>>     rows.append(row)
>>> # xdoctest: +REQUIRES(module:pandas)
>>> import pandas as pd
>>> df = pd.DataFrame(rows)
>>> for _, subdf in df.groupby('chunker'):
>>>     print(subdf)

static noborder(items, chunksize)

static cycle(items, chunksize)

static replicate(items, chunksize)

ubelt.cmd(command, shell=False, detach=False, verbose=0, tee=None, cwd=None, env=None, tee_backend='auto', check=False, **kwargs)

Executes a command in a subprocess.

The advantage of this wrapper around subprocess is that (1) you control if the subprocess prints to stdout, (2) the text written to stdout and stderr is returned for parsing, (3) cross platform behavior that lets you specify the command as a string or tuple regardless of whether or not shell=True. (4) ability to detach, return the process object and allow the process to run in the background (eventually we may return a Future object instead).

Parameters

• command (str | List[str]) – bash-like command string or tuple of executable and args

• shell (bool, default=False) – if True, process is run in shell.

• detach (bool, default=False) – if True, process is detached and run in background.

• verbose (int, default=0) – verbosity mode. Can be 0, 1, 2, or 3.

• tee (bool | None) – if True, simultaneously writes to stdout while capturing output from the command. If not specified, defaults to True if verbose > 0. If detach is True, then this argument is ignored.

• cwd (str | PathLike | None) – Path to run command. Defaults to current working directory if unspecified.

• env (Dict[str, str] | None) – environment passed to Popen

• tee_backend (str, default=’auto’) – backend for tee output. Valid choices are: “auto”, “select” (POSIX only), and “thread”.

• check (bool, default=False) – if True, check that the return code was zero before returning, otherwise raise a CalledProcessError. Does nothing if detach is True.

• **kwargs – only used to support deprecated arguments

Returns

info - information about command status. if detach is False info contains captured standard out, standard error, and the return code if detach is False info contains a reference to the process.

Return type

dict

Note

Inputs can either be text or tuple based. On UNIX we ensure conversion to text if shell=True, and to tuple if shell=False. On windows, the input is always text based. See [SO_33560364] for a potential cross-platform shlex solution for windows.

CommandLine

xdoctest -m ubelt.util_cmd cmd:6
python -c "import ubelt as ub; ub.cmd('ping localhost -c 2', verbose=2)"
pytest "$(python -c 'import ubelt; print(ubelt.util_cmd.__file__)')" -sv --xdoctest-verbose 2

References

SO_11495783

https://stackoverflow.com/questions/11495783/redirect-subprocess-stderr-to-stdout

SO_7729336

https://stackoverflow.com/questions/7729336/how-can-i-print-and-display-subprocess-stdout-and-stderr-output-without-distorti

SO_33560364

https://stackoverflow.com/questions/33560364/python-windows-parsing-command-lines-with-shlex

Example

>>> import ubelt as ub
>>> info = ub.cmd(('echo', 'simple cmdline interface'), verbose=1)
simple cmdline interface
>>> assert info['ret'] == 0
>>> assert info['out'].strip() == 'simple cmdline interface'
>>> assert info['err'].strip() == ''

Example

>>> import ubelt as ub
>>> info = ub.cmd('echo str noshell', verbose=0)
>>> assert info['out'].strip() == 'str noshell'

Example

>>> # windows echo will output extra single quotes
>>> import ubelt as ub
>>> info = ub.cmd(('echo', 'tuple noshell'), verbose=0)
>>> assert info['out'].strip().strip("'") == 'tuple noshell'

Example

>>> # Note this command is formatted to work on win32 and unix
>>> import ubelt as ub
>>> info = ub.cmd('echo str&&echo shell', verbose=0, shell=True)
>>> assert info['out'].strip() == 'str' + chr(10) + 'shell'

Example

>>> import ubelt as ub
>>> info = ub.cmd(('echo', 'tuple shell'), verbose=0, shell=True)
>>> assert info['out'].strip().strip("'") == 'tuple shell'

Example

>>> import pytest
>>> import ubelt as ub
>>> info = ub.cmd('echo hi', check=True)
>>> import subprocess
>>> with pytest.raises(subprocess.CalledProcessError):
>>>     ub.cmd('exit 1', check=True, shell=True)

Example

>>> import ubelt as ub
>>> from os.path import join, exists
>>> fpath1 = join(ub.get_app_cache_dir('ubelt'), 'cmdout1.txt')
>>> fpath2 = join(ub.get_app_cache_dir('ubelt'), 'cmdout2.txt')
>>> ub.delete(fpath1)
>>> ub.delete(fpath2)
>>> # Start up two processes that run simultaneously in the background
>>> info1 = ub.cmd(('touch', fpath1), detach=True)
>>> info2 = ub.cmd('echo writing2 > ' + fpath2, shell=True, detach=True)
>>> # Detached processes are running in the background
>>> # We can run other code while we wait for them.
>>> while not exists(fpath1):
...     pass
>>> while not exists(fpath2):
...     pass
>>> # communicate with the process before you finish
>>> # (otherwise you may leak a text wrapper)
>>> info1['proc'].communicate()
>>> info2['proc'].communicate()
>>> # Check that the process actually did finish
>>> assert (info1['proc'].wait()) == 0
>>> assert (info2['proc'].wait()) == 0
>>> # Check that the process did what we expect
>>> assert ub.readfrom(fpath1) == ''
>>> assert ub.readfrom(fpath2).strip() == 'writing2'

ubelt.codeblock(text)

Create a block of text that preserves all newlines and relative indentation

Wraps multiline string blocks and returns unindented code. Useful for templated code defined in indented parts of code.

Parameters

text (str) – typically a multiline string

Returns

the unindented string

Return type

str

Example

>>> import ubelt as ub
>>> # Simulate an indented part of code
>>> if True:
>>>     # notice the indentation on this will be normal
>>>     codeblock_version = ub.codeblock(
...             '''
...             def foo():
...                 return 'bar'
...             '''
...         )
>>>     # notice the indentation and newlines on this will be odd
>>>     normal_version = ('''
...         def foo():
...             return 'bar'
...     ''')
>>> assert normal_version != codeblock_version
>>> print('Without codeblock')
>>> print(normal_version)
>>> print('With codeblock')
>>> print(codeblock_version)

ubelt.color_text(text, color)

Colorizes text a single color using ansi tags.

Parameters

• text (str) – text to colorize

• color (str) – color code. different systems may have different colors. commonly available colors are: ‘red’, ‘brown’, ‘yellow’, ‘green’, ‘blue’, ‘black’, and ‘white’.

Returns

text - colorized text. If pygments is not installed plain text is returned.

Return type

str

Example

>>> text = 'raw text'
>>> import pytest
>>> import ubelt as ub
>>> if ub.modname_to_modpath('pygments'):
>>>     # Colors text only if pygments is installed
>>>     ansi_text = ub.ensure_unicode(color_text(text, 'red'))
>>>     prefix = ub.ensure_unicode('\x1b[31')
>>>     print('prefix = {!r}'.format(prefix))
>>>     print('ansi_text = {!r}'.format(ansi_text))
>>>     assert ansi_text.startswith(prefix)
>>>     assert color_text(text, None) == 'raw text'
>>> else:
>>>     # Otherwise text passes through unchanged
>>>     assert color_text(text, 'red') == 'raw text'
>>>     assert color_text(text, None) == 'raw text'

ubelt.compatible(config, func, start=0)

Take the subset of dict items that can be passed to function as kwargs

Parameters

• config (Dict[str, Any]) – a flat configuration dictionary

• func (Callable) – a function or method

• start (int, default=0) – Only take args after this position. Set to 1 if calling with an unbound method to avoid the self argument.

Returns

a subset of config that only contains items compatible with the signature of func.

Return type

Dict[str, Any]

Example

>>> # An example use case is to select a subset of of a config
>>> # that can be passed to some function as kwargs
>>> import ubelt as ub
>>> # Define a function with args that match some keys in a config.
>>> def func(a, e, f):
>>>     return a * e * f
>>> # Define a config that has a superset of items needed by the func
>>> config = {
...   'a': 2, 'b': 3, 'c': 7,
...   'd': 11, 'e': 13, 'f': 17,
... }
>>> # Call the function only with keys that are compatible
>>> func(**ub.compatible(config, func))
442

Example

>>> # Test case with kwargs
>>> import ubelt as ub
>>> def func(a, e, f, *args, **kwargs):
>>>     return a * e * f
>>> config = {
...   'a': 2, 'b': 3, 'c': 7,
...   'd': 11, 'e': 13, 'f': 17,
... }
>>> func(**ub.compatible(config, func))

ubelt.compress(items, flags)

Selects from items where the corresponding value in flags is True.

Parameters

• items (Iterable[Any]) – a sequence to select items from

• flags (Iterable[bool]) – corresponding sequence of bools

Returns

a subset of masked items

Return type

Iterable[Any]

Notes

This function is based on numpy.compress(), but is pure Python and swaps the condition and array argument to be consistent with ubelt.take().

This is equivalent to itertools.compress().

Example

>>> import ubelt as ub
>>> items = [1, 2, 3, 4, 5]
>>> flags = [False, True, True, False, True]
>>> list(ub.compress(items, flags))
[2, 3, 5]

ubelt.compressuser(path, home='~')

Inverse of os.path.expanduser().

Parameters

• path (str | PathLike) – path in system file structure

• home (str, default=’~’) – symbol used to replace the home path. Defaults to ‘~’, but you might want to use ‘$HOME’ or ‘%USERPROFILE%’ instead.

Returns

path: shortened path replacing the home directory with a tilde

Return type

str

Example

>>> from os.path import join
>>> path = expanduser('~')
>>> assert path != '~'
>>> assert compressuser(path) == '~'
>>> assert compressuser(path + '1') == path + '1'
>>> assert compressuser(path + '/1') == join('~', '1')
>>> assert compressuser(path + '/1', '$HOME') == join('$HOME', '1')

ubelt.ddict

alias of collections.defaultdict

ubelt.delete(path, verbose=False)

Removes a file or recursively removes a directory. If a path does not exist, then this is does nothing.

Parameters

• path (str | PathLike) – file or directory to remove

• verbose (bool) – if True prints what is being done

SeeAlso:

send2trash -

A cross-platform Python package for sending files to the trash instead of irreversibly deleting them.

ubelt.util_path.Path.delete()

Notes

This can call os.unlink(), os.rmdir(), or shutil.rmtree(), depending on what path references on the filesystem. (On windows may also call a custom ubelt._win32_links._win32_rmtree()).

Example

>>> import ubelt as ub
>>> from os.path import join
>>> base = ub.ensure_app_cache_dir('ubelt', 'delete_test')
>>> dpath1 = ub.ensuredir(join(base, 'dir'))
>>> ub.ensuredir(join(base, 'dir', 'subdir'))
>>> ub.touch(join(base, 'dir', 'to_remove1.txt'))
>>> fpath1 = join(base, 'dir', 'subdir', 'to_remove3.txt')
>>> fpath2 = join(base, 'dir', 'subdir', 'to_remove2.txt')
>>> ub.touch(fpath1)
>>> ub.touch(fpath2)
>>> assert all(map(exists, (dpath1, fpath1, fpath2)))
>>> ub.delete(fpath1)
>>> assert all(map(exists, (dpath1, fpath2)))
>>> assert not exists(fpath1)
>>> ub.delete(dpath1)
>>> assert not any(map(exists, (dpath1, fpath1, fpath2)))

Example

>>> import ubelt as ub
>>> from os.path import exists, join
>>> dpath = ub.ensure_app_cache_dir('ubelt', 'delete_test2')
>>> dpath1 = ub.ensuredir(join(dpath, 'dir'))
>>> fpath1 = ub.touch(join(dpath1, 'to_remove.txt'))
>>> assert exists(fpath1)
>>> ub.delete(dpath)
>>> assert not exists(fpath1)

ubelt.dict_diff(*args)

Dictionary set extension for set.difference()

Constructs a dictionary that contains any of the keys in the first arg, which are not in any of the following args.

Parameters

*args (List[Dict[KT, VT] | Iterable[KT]]) – A sequence of dictionaries (or sets of keys). The first argument should always be a dictionary, but the subsequent arguments can just be sets of keys.

Returns

OrderedDict if the first argument is an OrderedDict, otherwise dict

Return type

Dict[KT, VT] | OrderedDict[KT, VT]

Todo

• [ ] Add inplace keyword argument, which modifies the first dictionary inplace.

Example

>>> import ubelt as ub
>>> ub.dict_diff({'a': 1, 'b': 1}, {'a'}, {'c'})
{'b': 1}
>>> ub.dict_diff(odict([('a', 1), ('b', 2)]), odict([('c', 3)]))
OrderedDict([('a', 1), ('b', 2)])
>>> ub.dict_diff()
{}
>>> ub.dict_diff({'a': 1, 'b': 2}, {'c'})

ubelt.dict_hist(items, weights=None, ordered=False, labels=None)

Builds a histogram of items, counting the number of time each item appears in the input.

Parameters

• items (Iterable[T]) – hashable items (usually containing duplicates)

• weights (Iterable[float], default=None) – Corresponding weights for each item.

• ordered (bool, default=False) – If True the result is ordered by frequency.

• labels (Iterable[T], default=None) – Expected labels. Allows this function to pre-initialize the histogram. If specified the frequency of each label is initialized to zero and items can only contain items specified in labels.

Returns

dictionary where the keys are unique elements from items, and the values are the number of times the item appears in items.

Return type

dict[T, int]

Example

>>> import ubelt as ub
>>> items = [1, 2, 39, 900, 1232, 900, 1232, 2, 2, 2, 900]
>>> hist = ub.dict_hist(items)
>>> print(ub.repr2(hist, nl=0))
{1: 1, 2: 4, 39: 1, 900: 3, 1232: 2}

Example

>>> import ubelt as ub
>>> items = [1, 2, 39, 900, 1232, 900, 1232, 2, 2, 2, 900]
>>> hist1 = ub.dict_hist(items)
>>> hist2 = ub.dict_hist(items, ordered=True)
>>> try:
>>>     hist3 = ub.dict_hist(items, labels=[])
>>> except KeyError:
>>>     pass
>>> else:
>>>     raise AssertionError('expected key error')
>>> weights = [1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1]
>>> hist4 = ub.dict_hist(items, weights=weights)
>>> print(ub.repr2(hist1, nl=0))
{1: 1, 2: 4, 39: 1, 900: 3, 1232: 2}
>>> print(ub.repr2(hist4, nl=0))
{1: 1, 2: 4, 39: 1, 900: 1, 1232: 0}

ubelt.dict_isect(*args)

Dictionary set extension for set.intersection()

Constructs a dictionary that contains keys common between all inputs. The returned values will only belong to the first dictionary.

Parameters

*args (List[Dict[KT, VT] | Iterable[KT]]) – A sequence of dictionaries (or sets of keys). The first argument should always be a dictionary, but the subsequent arguments can just be sets of keys.

Returns

OrderedDict if the first argument is an OrderedDict, otherwise dict

Return type

Dict[KT, VT] | OrderedDict[KT, VT]

Note

This function can be used as an alternative to dict_subset() where any key not in the dictionary is ignored. See the following example:

>>> import ubelt as ub
>>> # xdoctest: +IGNORE_WANT
>>> ub.dict_isect({'a': 1, 'b': 2, 'c': 3}, ['a', 'c', 'd'])
{'a': 1, 'c': 3}

Example

>>> import ubelt as ub
>>> ub.dict_isect({'a': 1, 'b': 1}, {'b': 2, 'c': 2})
{'b': 1}
>>> ub.dict_isect(odict([('a', 1), ('b', 2)]), odict([('c', 3)]))
OrderedDict()
>>> ub.dict_isect()
{}

ubelt.dict_subset(dict_, keys, default=NoParam, cls=<class 'collections.OrderedDict'>)

Get a subset of a dictionary

Parameters

• dict_ (Dict[KT, VT]) – superset dictionary

• keys (Iterable[KT]) – keys to take from dict_

• default (Optional[object] | util_const._NoParamType) – if specified uses default if keys are missing.

• cls (Type[Dict], default=OrderedDict) – type of the returned dictionary.

Returns

subset dictionary

Return type

Dict[KT, VT]

SeeAlso:

dict_isect() - similar functionality, but ignores missing keys

Example

>>> import ubelt as ub
>>> dict_ = {'K': 3, 'dcvs_clip_max': 0.2, 'p': 0.1}
>>> keys = ['K', 'dcvs_clip_max']
>>> subdict_ = ub.dict_subset(dict_, keys)
>>> print(ub.repr2(subdict_, nl=0))
{'K': 3, 'dcvs_clip_max': 0.2}

ubelt.dict_take(dict_, keys, default=NoParam)

Generates values from a dictionary

Parameters

• dict_ (Mapping) – a dictionary to take from

• keys (Iterable) – the keys to take

• default (object, optional) – if specified uses default if keys are missing

Example

>>> import ubelt as ub
>>> dict_ = {1: 'a', 2: 'b', 3: 'c'}
>>> keys = [1, 2, 3, 4, 5]
>>> result = list(ub.dict_take(dict_, keys, None))
>>> assert result == ['a', 'b', 'c', None, None]

Example

>>> import ubelt as ub
>>> dict_ = {1: 'a', 2: 'b', 3: 'c'}
>>> keys = [1, 2, 3, 4, 5]
>>> try:
>>>     print(list(ub.dict_take(dict_, keys)))
>>>     raise AssertionError('did not get key error')
>>> except KeyError:
>>>     print('correctly got key error')

ubelt.dict_union(*args)

Dictionary set extension for set.union

Combines the disjoint keys in multiple dictionaries. For intersecting keys, dictionaries towards the end of the sequence are given precedence.

Parameters

*args (List[Dict]) – a sequence of dictionaries

Returns

OrderedDict if the first argument is an OrderedDict, otherwise dict

Return type

Dict | OrderedDict

SeeAlso:

collections.ChainMap() - a standard python builtin data structure that provides a view that treats multiple dicts as a single dict. https://docs.python.org/3/library/collections.html#chainmap-objects

Example

>>> import ubelt as ub
>>> result = ub.dict_union({'a': 1, 'b': 1}, {'b': 2, 'c': 2})
>>> assert result == {'a': 1, 'b': 2, 'c': 2}
>>> ub.dict_union(
>>>     ub.odict([('a', 1), ('b', 2)]),
>>>     ub.odict([('c', 3), ('d', 4)]))
OrderedDict([('a', 1), ('b', 2), ('c', 3), ('d', 4)])
>>> ub.dict_union()
{}

ubelt.download(url, fpath=None, dpath=None, fname=None, hash_prefix=None, hasher='sha512', chunksize=8192, verbose=1, timeout=NoParam, progkw=None)

Downloads a url to a file on disk.

If unspecified the location and name of the file is chosen automatically. A hash_prefix can be specified to verify the integrity of the downloaded data. This function will download the data every time its called. For cached downloading see grabdata.

Parameters

• url (str) – The url to download.

• fpath (Optional[str | PathLike | io.BytesIO]) – The path to download to. Defaults to basename of url and ubelt’s application cache. If this is a io.BytesIO object then information is directly written to this object (note this prevents the use of temporary files).

• dpath (Optional[PathLike]) – where to download the file. If unspecified appname is used to determine this. Mutually exclusive with fpath.

• fname (Optional[str]) – What to name the downloaded file. Defaults to the url basename. Mutually exclusive with fpath.

• hash_prefix (None | str) – If specified, download will retry / error if the file hash does not match this value. Defaults to None.

• hasher (str | Hasher) – If hash_prefix is specified, this indicates the hashing algorithm to apply to the file. Defaults to sha512.

• chunksize (int, default=2 * 13*) – Download chunksize.

• verbose (int, default=1) – Verbosity level 0 or 1.

• timeout (float, default=NoParam) – Specify timeout in seconds for urllib.request.urlopen(). (if not specified, the global default timeout setting will be used) This only works for HTTP, HTTPS and FTP connections for blocking operations like the connection attempt.

• progkw (Dict | None) – if specified provides extra arguments to the progress iterator

Returns

fpath - path to the downloaded file.

Return type

str | PathLike

Raises

• URLError - if there is problem downloading the url –

• RuntimeError - if the hash does not match the hash_prefix –

Note

Based largely on code in pytorch [TorchDL] with modifications influenced by other resources [Shichao_2012] [SO_15644964] [SO_16694907].

References

Shichao_2012

https://blog.shichao.io/2012/10/04/progress_speed_indicator_for_urlretrieve_in_python.html

SO_15644964

http://stackoverflow.com/questions/15644964/python-progress-bar-and-downloads

SO_16694907

http://stackoverflow.com/questions/16694907/how-to-download-large-file-in-python-with-requests-py

TorchDL

https://github.com/pytorch/pytorch/blob/2787f1d8edbd4aadd4a8680d204341a1d7112e2d/torch/hub.py#L347

Example

>>> # xdoctest: +REQUIRES(--network)
>>> from ubelt.util_download import *  # NOQA
>>> url = 'http://i.imgur.com/rqwaDag.png'
>>> fpath = download(url)
>>> print(basename(fpath))
rqwaDag.png

Example

>>> # xdoctest: +REQUIRES(--network)
>>> import ubelt as ub
>>> import io
>>> url = 'http://i.imgur.com/rqwaDag.png'
>>> file = io.BytesIO()
>>> fpath = ub.download(url, file)
>>> file.seek(0)
>>> data = file.read()
>>> assert ub.hash_data(data, hasher='sha1').startswith('f79ea24571')

Example

>>> # xdoctest: +REQUIRES(--network)
>>> url = 'http://i.imgur.com/rqwaDag.png'
>>> fpath = download(url, hasher='sha1', hash_prefix='f79ea24571da6ddd2ba12e3d57b515249ecb8a35')
Downloading url='http://i.imgur.com/rqwaDag.png' to fpath=...rqwaDag.png
...
...1233/1233... rate=... Hz, eta=..., total=...

Example

>>> # xdoctest: +REQUIRES(--network)
>>> import pytest
>>> import ubelt as ub
>>> url = 'http://i.imgur.com/rqwaDag.png'
>>> #fpath = download(url, hasher='sha1', hash_prefix='f79ea24571da6ddd2ba12e3d57b515249ecb8a35')
>>> # test download from girder
>>> #url = 'https://data.kitware.com/api/v1/item/5b4039308d777f2e6225994c/download'
>>> #ub.download(url, hasher='sha512', hash_prefix='c98a46cb31205cf')
>>> with pytest.raises(RuntimeError):
>>>     ub.download(url, hasher='sha512', hash_prefix='BAD_HASH')

ubelt.dzip(items1, items2, cls=<class 'dict'>)

Zips elementwise pairs between items1 and items2 into a dictionary.

Values from items2 can be broadcast onto items1.

Parameters

• items1 (Iterable[KT]) – full sequence

• items2 (Iterable[VT]) – can either be a sequence of one item or a sequence of equal length to items1

• cls (Type[dict], default=dict) – dictionary type to use.

Returns

similar to dict(zip(items1, items2)).

Return type

Dict[KT, VT]

Example

>>> import ubelt as ub
>>> assert ub.dzip([1, 2, 3], [4]) == {1: 4, 2: 4, 3: 4}
>>> assert ub.dzip([1, 2, 3], [4, 4, 4]) == {1: 4, 2: 4, 3: 4}
>>> assert ub.dzip([], [4]) == {}

ubelt.editfile(fpath, verbose=True)

DEPRECATED: This has been ported to xdev, please use that version.

Opens a file or code corresponding to a live python object in your preferred visual editor. This function is mainly useful in an interactive IPython session.

The visual editor is determined by the VISUAL environment variable. If this is not specified it defaults to gvim.

Parameters

• fpath (PathLike) – a file path or python module / function

• verbose (int) – verbosity

Example

>>> # xdoctest: +SKIP
>>> # This test interacts with a GUI frontend, not sure how to test.
>>> import ubelt as ub
>>> ub.editfile(ub.util_platform.__file__)
>>> ub.editfile(ub)
>>> ub.editfile(ub.editfile)

ubelt.ensure_app_cache_dir(appname, *args)

Calls get_app_cache_dir() but ensures the directory exists.

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

the path to the ensured directory

Return type

str

SeeAlso:

get_app_cache_dir()

Example

>>> import ubelt as ub
>>> dpath = ub.ensure_app_cache_dir('ubelt')
>>> assert exists(dpath)

ubelt.ensure_app_config_dir(appname, *args)

Calls get_app_config_dir() but ensures the directory exists.

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

the path to the ensured directory

Return type

str

SeeAlso:

get_app_config_dir()

Example

>>> import ubelt as ub
>>> dpath = ub.ensure_app_config_dir('ubelt')
>>> assert exists(dpath)

ubelt.ensure_app_data_dir(appname, *args)

Calls get_app_data_dir() but ensures the directory exists.

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

the path to the ensured directory

Return type

str

SeeAlso:

get_app_data_dir()

Example

>>> import ubelt as ub
>>> dpath = ub.ensure_app_data_dir('ubelt')
>>> assert exists(dpath)

ubelt.ensure_app_resource_dir(appname, *args)

Calls get_app_resource_dir but ensures the directory exists.

DEPRECATED in favor of ensure_app_config_dir / ensure_app_data_dir

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

SeeAlso:

get_app_resource_dir

ubelt.ensure_unicode(text)

Casts bytes into utf8 (mostly for python2 compatibility)

Parameters

text (str | bytes) – text to ensure is decoded as unicode

Returns

str

References

[SO_12561063] http://stackoverflow.com/questions/12561063/extract-data-from-file

Example

>>> from ubelt.util_str import *
>>> import codecs  # NOQA
>>> assert ensure_unicode('my ünicôdé strįng') == 'my ünicôdé strįng'
>>> assert ensure_unicode('text1') == 'text1'
>>> assert ensure_unicode('text1'.encode('utf8')) == 'text1'
>>> assert ensure_unicode('text1'.encode('utf8')) == 'text1'
>>> assert (codecs.BOM_UTF8 + 'text»¿'.encode('utf8')).decode('utf8')

ubelt.ensuredir(dpath, mode=1023, verbose=0, recreate=False)

Ensures that directory will exist. Creates new dir with sticky bits by default

Parameters

• dpath (str | PathLike | Tuple[str | PathLike]) – dir to ensure. Can also be a tuple to send to join

• mode (int, default=0o1777) – octal mode of directory

• verbose (int, default=0) – verbosity

• recreate (bool, default=False) – if True removes the directory and all of its contents and creates a fresh new directory. USE CAREFULLY.

Returns

path - the ensured directory

Return type

str

SeeAlso:

ubelt.Path.ensuredir()

Note

This function is not thread-safe in Python2

Example

>>> from ubelt.util_path import *  # NOQA
>>> import ubelt as ub
>>> cache_dpath = ub.ensure_app_cache_dir('ubelt')
>>> dpath = join(cache_dpath, 'ensuredir')
>>> if exists(dpath):
...     os.rmdir(dpath)
>>> assert not exists(dpath)
>>> ub.ensuredir(dpath)
>>> assert exists(dpath)
>>> os.rmdir(dpath)

ubelt.expandpath(path)

Shell-like environment variable and tilde path expansion.

Less aggressive than truepath. Only expands environs and tilde. Does not change relative paths to absolute paths.

Parameters

path (str | PathLike) – string representation of a path

Returns

expanded path

Return type

str

Example

>>> from ubelt.util_path import *  # NOQA
>>> import ubelt as ub
>>> assert normpath(ub.expandpath('~/foo')) == join(ub.userhome(), 'foo')
>>> assert ub.expandpath('foo') == 'foo'

ubelt.find_duplicates(items, k=2, key=None)

Find all duplicate items in a list.

Search for all items that appear more than k times and return a mapping from each (k)-duplicate item to the positions it appeared in.

Parameters

• items (Iterable[T]) – hashable items possibly containing duplicates

• k (int, default=2) – only return items that appear at least k times.

• key (Callable[[T], Any], default=None) – Returns indices where key(items[i]) maps to a particular value at least k times.

Returns

maps each duplicate item to the indices at which it appears

Return type

dict[T, List[int]]

Notes

Similar to more_itertools.duplicates_everseen(), more_itertools.duplicates_justseen().

Example

>>> import ubelt as ub
>>> items = [0, 0, 1, 2, 3, 3, 0, 12, 2, 9]
>>> duplicates = ub.find_duplicates(items)
>>> # Duplicates are a mapping from each item that occurs 2 or more
>>> # times to the indices at which they occur.
>>> assert duplicates == {0: [0, 1, 6], 2: [3, 8], 3: [4, 5]}
>>> # You can set k=3 if you want to don't mind duplicates but you
>>> # want to find triplicates or quadruplets etc.
>>> assert ub.find_duplicates(items, k=3) == {0: [0, 1, 6]}

Example

>>> import ubelt as ub
>>> items = [0, 0, 1, 2, 3, 3, 0, 12, 2, 9]
>>> # note: k can less then 2
>>> duplicates = ub.find_duplicates(items, k=0)
>>> print(ub.repr2(duplicates, nl=0))
{0: [0, 1, 6], 1: [2], 2: [3, 8], 3: [4, 5], 9: [9], 12: [7]}

Example

>>> import ubelt as ub
>>> items = [10, 11, 12, 13, 14, 15, 16]
>>> duplicates = ub.find_duplicates(items, key=lambda x: x // 2)
>>> print(ub.repr2(duplicates, nl=0))
{5: [0, 1], 6: [2, 3], 7: [4, 5]}

ubelt.find_exe(name, multi=False, path=None)

Locate a command.

Search your local filesystem for an executable and return the first matching file with executable permission.

Parameters

• name (str | PathLike) – globstr of matching filename

• multi (bool, default=False) – if True return all matches instead of just the first.

• path (str | PathLike | Iterable[str | PathLike] | None, default=None) – overrides the system PATH variable.

Returns

returns matching executable(s).

Return type

str | List[str] | None

SeeAlso:

shutil.which() - which is available in Python 3.3+.

Note

This is essentially the which UNIX command

References

SO_377017

https://stackoverflow.com/questions/377017/test-if-executable-exists-in-python/377028#377028

shutil_which

https://docs.python.org/dev/library/shutil.html#shutil.which

Example

>>> find_exe('ls')
>>> find_exe('ping')
>>> assert find_exe('which') == find_exe(find_exe('which'))
>>> find_exe('which', multi=True)
>>> find_exe('ping', multi=True)
>>> find_exe('cmake', multi=True)
>>> find_exe('nvcc', multi=True)
>>> find_exe('noexist', multi=True)

Example

>>> import ubelt as ub
>>> assert not ub.find_exe('noexist', multi=False)
>>> assert ub.find_exe('ping', multi=False) or ub.find_exe('ls', multi=False)
>>> assert not ub.find_exe('noexist', multi=True)
>>> assert ub.find_exe('ping', multi=True) or ub.find_exe('ls', multi=True)

Benchmark:

>>> # xdoctest: +IGNORE_WANT
>>> import ubelt as ub
>>> import shutil
>>> for timer in ub.Timerit(100, bestof=10, label='ub.find_exe'):
>>>     ub.find_exe('which')
>>> for timer in ub.Timerit(100, bestof=10, label='shutil.which'):
>>>     shutil.which('which')
Timed best=58.71 µs, mean=59.64 ± 0.96 µs for ub.find_exe
Timed best=72.75 µs, mean=73.07 ± 0.22 µs for shutil.which

ubelt.find_path(name, path=None, exact=False)

Search for a file or directory on your local filesystem by name (file must be in a directory specified in a PATH environment variable)

Parameters

• name (str | PathLike) – file name to match. If exact is False this may be a glob pattern

• path (str | Iterable[str | PathLike], default=None) – list of directories to search either specified as an os.pathsep separated string or a list of directories. Defaults to environment PATH.

• exact (bool, default=False) – if True, only returns exact matches.

Yields

str – candidate - a path that matches name

Note

Running with name='' (i.e. ub.find_path('')) will simply yield all directories in your PATH.

Note

For recursive behavior set path=(d for d, _, _ in os.walk('.')), where ‘.’ might be replaced by the root directory of interest.

Example

>>> list(find_path('ping', exact=True))
>>> list(find_path('bin'))
>>> list(find_path('*cc*'))
>>> list(find_path('cmake*'))

Example

>>> import ubelt as ub
>>> from os.path import dirname
>>> path = dirname(dirname(ub.util_platform.__file__))
>>> res = sorted(find_path('ubelt/util_*.py', path=path))
>>> assert len(res) >= 10
>>> res = sorted(find_path('ubelt/util_platform.py', path=path, exact=True))
>>> print(res)
>>> assert len(res) == 1

ubelt.flatten(nested)

Transforms a nested iterable into a flat iterable.

Parameters

nested (Iterable[Iterable[Any]]) – list of lists

Returns

flattened items

Return type

Iterable[Any]

Notes

Equivalent to more_itertools.flatten() and itertools.chain.from_iterable().

Example

>>> import ubelt as ub
>>> nested = [['a', 'b'], ['c', 'd']]
>>> list(ub.flatten(nested))
['a', 'b', 'c', 'd']

ubelt.get_app_cache_dir(appname, *args)

Returns a writable directory for an application. This should be used for temporary deletable data.

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

the path to the ensured directory

Return type

str

Returns

dpath - writable cache directory for this application

Return type

str

SeeAlso:

ensure_app_cache_dir()

ubelt.get_app_config_dir(appname, *args)

Returns a writable directory for an application This should be used for persistent configuration files.

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

dpath - writable config directory for this application

Return type

str

SeeAlso:

ensure_app_config_dir()

ubelt.get_app_data_dir(appname, *args)

Returns a writable directory for an application. This should be used for temporary deletable data.

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

dpath - writable data directory for this application

Return type

str

SeeAlso:

ensure_app_data_dir()

ubelt.get_app_resource_dir(appname, *args)

Returns a writable directory for an application This should be used for persistent configuration files.

DEPRECATED in favor of get_app_config_dir / get_app_data_dir

Parameters

• appname (str) – the name of the application

• *args – any other subdirectories may be specified

Returns

dpath: writable resource directory for this application

Return type

PathLike

SeeAlso:

ensure_app_resource_dir

ubelt.grabdata(url, fpath=None, dpath=None, fname=None, redo=False, verbose=1, appname=None, hash_prefix=None, hasher='sha512', **download_kw)

Downloads a file, caches it, and returns its local path.

If unspecified the location and name of the file is chosen automatically. A hash_prefix can be specified to verify the integrity of the downloaded data.

Parameters

• url (str) – url to the file to download

• fpath (Optional[str | PathLike]) – The full path to download the file to. If unspecified, the arguments dpath and fname are used to determine this.

• dpath (Optional[str | PathLike]) – where to download the file. If unspecified appname is used to determine this. Mutually exclusive with fpath.

• fname (Optional[str]) – What to name the downloaded file. Defaults to the url basename. Mutually exclusive with fpath.

• redo (bool, default=False) – if True forces redownload of the file

• verbose (bool, default=True) – verbosity flag

• appname (str) – set dpath to ub.get_app_cache_dir(appname). Mutually exclusive with dpath and fpath.

• hash_prefix (None | str) – If specified, grabdata verifies that this matches the hash of the file, and then saves the hash in a adjacent file to certify that the download was successful. Defaults to None.

• hasher (str | Hasher) – If hash_prefix is specified, this indicates the hashing algorithm to apply to the file. Defaults to sha512.

• **download_kw – additional kwargs to pass to ubelt.util_download.download()

Returns

fpath - path to downloaded or cached file.

Return type

str | PathLike

CommandLine

xdoctest -m ubelt.util_download grabdata --network

Example

>>> # xdoctest: +REQUIRES(--network)
>>> import ubelt as ub
>>> url = 'http://i.imgur.com/rqwaDag.png'
>>> fpath = ub.grabdata(url, fname='mario.png')
>>> result = basename(fpath)
>>> print(result)
mario.png

Example

>>> # xdoctest: +REQUIRES(--network)
>>> import ubelt as ub
>>> fname = 'foo.bar'
>>> url = 'http://i.imgur.com/rqwaDag.png'
>>> prefix1 = '944389a39dfb8fa9'
>>> fpath = ub.grabdata(url, fname=fname, hash_prefix=prefix1)
>>> stamp_fpath = fpath + '.sha512.hash'
>>> assert ub.readfrom(stamp_fpath) == prefix1
>>> # Check that the download doesn't happen again
>>> fpath = ub.grabdata(url, fname=fname, hash_prefix=prefix1)
>>> # todo: check file timestamps have not changed
>>> #
>>> # Check redo works with hash
>>> fpath = ub.grabdata(url, fname=fname, hash_prefix=prefix1, redo=True)
>>> # todo: check file timestamps have changed
>>> #
>>> # Check that a redownload occurs when the stamp is changed
>>> with open(stamp_fpath, 'w') as file:
>>>     file.write('corrupt-stamp')
>>> fpath = ub.grabdata(url, fname=fname, hash_prefix=prefix1)
>>> assert ub.readfrom(stamp_fpath) == prefix1
>>> #
>>> # Check that a redownload occurs when the stamp is removed
>>> ub.delete(stamp_fpath)
>>> with open(fpath, 'w') as file:
>>>     file.write('corrupt-data')
>>> assert not ub.hash_file(fpath, base='hex', hasher='sha512').startswith(prefix1)
>>> fpath = ub.grabdata(url, fname=fname, hash_prefix=prefix1)
>>> assert ub.hash_file(fpath, base='hex', hasher='sha512').startswith(prefix1)
>>> #
>>> # Check that requesting new data causes redownload
>>> #url2 = 'https://data.kitware.com/api/v1/item/5b4039308d777f2e6225994c/download'
>>> #prefix2 = 'c98a46cb31205cf'  # hack SSL
>>> url2 = 'http://i.imgur.com/rqwaDag.png'
>>> prefix2 = '944389a39dfb8fa9'
>>> fpath = ub.grabdata(url2, fname=fname, hash_prefix=prefix2)
>>> assert ub.readfrom(stamp_fpath) == prefix2

ubelt.group_items(items, key)

Groups a list of items by group id.

Parameters

• items (Iterable[VT]) – a list of items to group

• key (Iterable[KT] | Callable[[VT], KT]) – either a corresponding list of group-ids for each item or a function used to map each item to a group-id.

Returns

a mapping from each group id to the list of corresponding items

Return type

dict[KT, List[VT]]

Example

>>> import ubelt as ub
>>> items    = ['ham',     'jam',   'spam',     'eggs',    'cheese', 'banana']
>>> groupids = ['protein', 'fruit', 'protein',  'protein', 'dairy',  'fruit']
>>> id_to_items = ub.group_items(items, groupids)
>>> print(ub.repr2(id_to_items, nl=0))
{'dairy': ['cheese'], 'fruit': ['jam', 'banana'], 'protein': ['ham', 'spam', 'eggs']}

ubelt.hash_data(data, hasher=NoParam, base=NoParam, types=False, hashlen=NoParam, convert=False, extensions=None)

Get a unique hash depending on the state of the data.

Parameters

• data (object) – Any sort of loosely organized data

• hasher (str | Hasher, default=’sha512’) – string code or a hash algorithm from hashlib. Valid hashing algorithms are defined by hashlib.algorithms_guaranteed (e.g. ‘sha1’, ‘sha512’, ‘md5’) as well as ‘xxh32’ and ‘xxh64’ if xxhash is installed.

• base (List[str] | str, default=’hex’) – list of symbols or shorthand key. Valid keys are ‘abc’, ‘hex’, and ‘dec’.

• types (bool) – If True data types are included in the hash, otherwise only the raw data is hashed. Defaults to False.

• hashlen (int) – Maximum number of symbols in the returned hash. If not specified, all are returned. DEPRECATED. Use slice syntax instead.

• convert (bool, default=True) – if True, try and convert the data to json an the json is hashed instead. This can improve runtime in some instances, however the hash may differ from the case where convert=False.

• extensions (HashableExtensions) – a custom HashableExtensions instance that can overwrite or define how different types of objects are hashed.

Note

The types allowed are specified by the HashableExtensions object. By default ubelt will register:

OrderedDict, uuid.UUID, np.random.RandomState, np.int64, np.int32, np.int16, np.int8, np.uint64, np.uint32, np.uint16, np.uint8, np.float16, np.float32, np.float64, np.float128, np.ndarray, bytes, str, int, float, long (in python2), list, tuple, set, and dict

Returns

text representing the hashed data

Return type

str

Note

The alphabet26 base is a pretty nice base, I recommend it. However we default to base='hex' because it is standard. You can try the alphabet26 base by setting base='abc'.

Example

>>> import ubelt as ub
>>> print(ub.hash_data([1, 2, (3, '4')], convert=False))
60b758587f599663931057e6ebdf185a...
>>> print(ub.hash_data([1, 2, (3, '4')], base='abc',  hasher='sha512')[:32])
hsrgqvfiuxvvhcdnypivhhthmrolkzej

ubelt.hash_file(fpath, blocksize=1048576, stride=1, maxbytes=None, hasher=NoParam, hashlen=NoParam, base=NoParam)

Hashes the data in a file on disk.

The results of this function agree with the standard UNIX commands (e.g. sha1sum, sha512sum, md5sum, etc…)

Parameters

• fpath (PathLike) – location of the file to be hashed.

• blocksize (int, default=2 * 20*) – Amount of data to read and hash at a time. There is a trade off and the optimal number will depend on specific hardware. This number was chosen to be optimal on a developer system. See “dev/bench_hash_file” for methodology to choose this number for your use case.

• stride (int, default=1) – strides > 1 skip data to hash, useful for faster hashing, but less accurate, also makes hash dependent on blocksize.

• maxbytes (int | None) – if specified, only hash the leading maxbytes of data in the file.

• hasher (str | Hasher, default=’sha512’) – string code or a hash algorithm from hashlib. Valid hashing algorithms are defined by hashlib.algorithms_guaranteed (e.g. ‘sha1’, ‘sha512’, ‘md5’) as well as ‘xxh32’ and ‘xxh64’ if xxhash is installed.

  TODO: add logic such that you can update an existing hasher

• hashlen (int) – maximum number of symbols in the returned hash. If not specified, all are returned. DEPRECATED. DO NOT USE.

• base (List[str] | str, default=’hex’) – list of symbols or shorthand key. Valid keys are ‘abc’, ‘hex’, and ‘dec’.

Note

For better hashes keep stride = 1. For faster hashes set stride > 1. Blocksize matters when stride > 1.

References

SO_3431825

http://stackoverflow.com/questions/3431825/md5-checksum-of-a-file

SO_5001893

http://stackoverflow.com/questions/5001893/when-to-use-sha-1-vs-sha-2

Example

>>> import ubelt as ub
>>> from os.path import join
>>> fpath = join(ub.ensure_app_cache_dir('ubelt'), 'tmp.txt')
>>> ub.writeto(fpath, 'foobar')
>>> print(ub.hash_file(fpath, hasher='sha1', base='hex'))
8843d7f92416211de9ebb963ff4ce28125932878

Example

>>> import ubelt as ub
>>> from os.path import join
>>> fpath = join(ub.ensure_app_cache_dir('ubelt'), 'tmp.txt')
>>> ub.writeto(fpath, 'foobar')
>>> print(ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=1000))
8843d7f92416211de9ebb963ff4ce28125932878

>>> # We have the ability to only hash at most ``maxbytes`` in a file
>>> ub.writeto(fpath, 'abcdefghijklmnop')
>>> h0 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=11, blocksize=3)
>>> h1 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=32, blocksize=3)
>>> h2 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=32, blocksize=32)
>>> h3 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=16, blocksize=1)
>>> h4 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=16, blocksize=18)
>>> assert h1 == h2 == h3 == h4
>>> assert h1 != h0

>>> # Using a stride makes the result dependent on the blocksize
>>> h0 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=11, blocksize=3, stride=2)
>>> h1 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=32, blocksize=3, stride=2)
>>> h2 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=32, blocksize=32, stride=2)
>>> h3 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=16, blocksize=1, stride=2)
>>> h4 = ub.hash_file(fpath, hasher='sha1', base='hex', maxbytes=16, blocksize=18, stride=2)
>>> assert h1 != h2 != h3
>>> assert h1 == h0
>>> assert h2 == h4

Example

>>> import ubelt as ub
>>> from os.path import join
>>> fpath = ub.touch(join(ub.ensure_app_cache_dir('ubelt'), 'empty_file'))
>>> # Test that the output is the same as sha1sum executable
>>> if ub.find_exe('sha1sum'):
>>>     want = ub.cmd(['sha1sum', fpath], verbose=2)['out'].split(' ')[0]
>>>     got = ub.hash_file(fpath, hasher='sha1')
>>>     print('want = {!r}'.format(want))
>>>     print('got = {!r}'.format(got))
>>>     assert want.endswith(got)
>>> # Do the same for sha512 sum and md5sum
>>> if ub.find_exe('sha512sum'):
>>>     want = ub.cmd(['sha512sum', fpath], verbose=2)['out'].split(' ')[0]
>>>     got = ub.hash_file(fpath, hasher='sha512')
>>>     print('want = {!r}'.format(want))
>>>     print('got = {!r}'.format(got))
>>>     assert want.endswith(got)
>>> if ub.find_exe('md5sum'):
>>>     want = ub.cmd(['md5sum', fpath], verbose=2)['out'].split(' ')[0]
>>>     got = ub.hash_file(fpath, hasher='md5')
>>>     print('want = {!r}'.format(want))
>>>     print('got = {!r}'.format(got))
>>>     assert want.endswith(got)

ubelt.highlight_code(text, lexer_name='python', **kwargs)

Highlights a block of text using ANSI tags based on language syntax.

Parameters

• text (str) – plain text to highlight

• lexer_name (str) – name of language. eg: python, docker, c++

• **kwargs – passed to pygments.lexers.get_lexer_by_name

Returns

text - highlighted text If pygments is not installed, the plain text is returned.

Return type

str

Example

>>> import ubelt as ub
>>> text = 'import ubelt as ub; print(ub)'
>>> new_text = ub.highlight_code(text)
>>> print(new_text)

ubelt.hzcat(args, sep='')

Horizontally concatenates strings preserving indentation

Concatenates a list of objects ensuring that the next item in the list is all the way to the right of any previous items.

Parameters

• args (List[str]) – strings to concatenate

• sep (str, default=’’) – separator

Example1:

>>> import ubelt as ub
>>> B = ub.repr2([[1, 2], [3, 457]], nl=1, cbr=True, trailsep=False)
>>> C = ub.repr2([[5, 6], [7, 8]], nl=1, cbr=True, trailsep=False)
>>> args = ['A = ', B, ' * ', C]
>>> print(ub.hzcat(args))
A = [[1, 2],   * [[5, 6],
     [3, 457]]    [7, 8]]

Example2:

>>> import ubelt as ub
>>> import unicodedata
>>> aa = unicodedata.normalize('NFD', 'á')  # a unicode char with len2
>>> B = ub.repr2([['θ', aa], [aa, aa, aa]], nl=1, si=True, cbr=True, trailsep=False)
>>> C = ub.repr2([[5, 6], [7, 'θ']], nl=1, si=True, cbr=True, trailsep=False)
>>> args = ['A', '=', B, '*', C]
>>> print(ub.hzcat(args, sep='｜'))
A｜=｜[[θ, á],   ｜*｜[[5, 6],
 ｜ ｜ [á, á, á]]｜ ｜ [7, θ]]

ubelt.identity(arg=None, *args, **kwargs)

The identity function. Simply returns the value of its first input.

All other inputs are ignored. Defaults to None if called without args.

Parameters

• arg (object, default=None) – some value

• *args – ignored

• **kwargs – ignored

Returns

arg - the same value

Return type

object

Example

>>> import ubelt as ub
>>> ub.identity(42)
42
>>> ub.identity(42, 42)
42
>>> ub.identity()
None

ubelt.import_module_from_name(modname)

Imports a module from its string name (i.e. __name__)

Parameters

modname (str) – module name

Returns

module

Return type

ModuleType

SeeAlso:

import_module_from_path()

Example

>>> # test with modules that won't be imported in normal circumstances
>>> # todo write a test where we guarantee this
>>> modname_list = [
>>>     'pickletools',
>>>     'lib2to3.fixes.fix_apply',
>>> ]
>>> #assert not any(m in sys.modules for m in modname_list)
>>> modules = [import_module_from_name(modname) for modname in modname_list]
>>> assert [m.__name__ for m in modules] == modname_list
>>> assert all(m in sys.modules for m in modname_list)

ubelt.import_module_from_path(modpath, index=- 1)

Imports a module via its path

Parameters

• modpath (str | PathLike) – Path to the module on disk or within a zipfile.

• index (int) – Location at which we modify PYTHONPATH if necessary. If your module name does not conflict, the safest value is -1, However, if there is a conflict, then use an index of 0. The default may change to 0 in the future.

Returns

the imported module

Return type

ModuleType

References

SO_67631

https://stackoverflow.com/questions/67631/import-module-given-path

Note

If the module is part of a package, the package will be imported first. These modules may cause problems when reloading via IPython magic

This can import a module from within a zipfile. To do this modpath should specify the path to the zipfile and the path to the module within that zipfile separated by a colon or pathsep. E.g. “/path/to/archive.zip:mymodule.pl”

Warning

It is best to use this with paths that will not conflict with previously existing modules.

If the modpath conflicts with a previously existing module name. And the target module does imports of its own relative to this conflicting path. In this case, the module that was loaded first will win.

For example if you try to import ‘/foo/bar/pkg/mod.py’ from the folder structure:

- foo/
  +- bar/
     +- pkg/
        +  __init__.py
        |- mod.py
        |- helper.py

If there exists another module named pkg already in sys.modules and mod.py does something like from . import helper, Python will assume helper belongs to the pkg module already in sys.modules. This can cause a NameError or worse — a incorrect helper module.

SeeAlso:

import_module_from_name()

Example

>>> import xdoctest
>>> modpath = xdoctest.__file__
>>> module = import_module_from_path(modpath)
>>> assert module is xdoctest

Example

>>> # Test importing a module from within a zipfile
>>> import zipfile
>>> from xdoctest import utils
>>> from os.path import join, expanduser, normpath
>>> dpath = expanduser('~/.cache/xdoctest')
>>> dpath = utils.ensuredir(dpath)
>>> #dpath = utils.TempDir().ensure()
>>> # Write to an external module named bar
>>> external_modpath = join(dpath, 'bar.py')
>>> # For pypy support we have to write this using with
>>> with open(external_modpath, 'w') as file:
>>>     file.write('testvar = 1')
>>> internal = 'folder/bar.py'
>>> # Move the external bar module into a zipfile
>>> zippath = join(dpath, 'myzip.zip')
>>> with zipfile.ZipFile(zippath, 'w') as myzip:
>>>     myzip.write(external_modpath, internal)
>>> # Import the bar module from within the zipfile
>>> modpath = zippath + ':' + internal
>>> modpath = zippath + os.path.sep + internal
>>> module = import_module_from_path(modpath)
>>> assert normpath(module.__name__) == normpath('folder/bar')
>>> assert module.testvar == 1

Example

>>> import pytest
>>> with pytest.raises(IOError):
>>>     import_module_from_path('does-not-exist')
>>> with pytest.raises(IOError):
>>>     import_module_from_path('does-not-exist.zip/')

ubelt.indent(text, prefix='    ')

Indents a block of text

Parameters

• text (str) – text to indent

• prefix (str, default = ‘ ‘) – prefix to add to each line

Returns

indented text

Return type

str

Example

>>> import ubelt as ub
>>> NL = chr(10)  # newline character
>>> text = 'Lorem ipsum' + NL + 'dolor sit amet'
>>> prefix = '    '
>>> result = ub.indent(text, prefix)
>>> assert all(t.startswith(prefix) for t in result.split(NL))

ubelt.indexable_allclose(dct1, dct2, rel_tol=1e-09, abs_tol=0.0, return_info=False)

Walks through two nested data structures and ensures that everything is roughly the same.

Parameters

• dct1 (dict) – a nested indexable item

• dct2 (dict) – a nested indexable item

• rel_tol (float) – maximum difference for being considered “close”, relative to the magnitude of the input values

• abs_tol (float) – maximum difference for being considered “close”, regardless of the magnitude of the input values

• return_info (bool, default=False) – if true, return extra info

Returns

A boolean result if return_info is false, otherwise a tuple of the boolean result and an “info” dict containing detailed results indicating what matched and what did not.

Return type

bool | Tuple[bool, Dict]

Example

>>> import ubelt as ub
>>> dct1 = {
>>>     'foo': [1.222222, 1.333],
>>>     'bar': 1,
>>>     'baz': [],
>>> }
>>> dct2 = {
>>>     'foo': [1.22222, 1.333],
>>>     'bar': 1,
>>>     'baz': [],
>>> }
>>> flag, return_info =  ub.indexable_allclose(dct1, dct2, return_info=True)
>>> print('return_info = {}'.format(ub.repr2(return_info, nl=1)))
>>> print('flag = {!r}'.format(flag))

>>> walker1 = return_info['walker1']
>>> for p1, v1, v2  in return_info['faillist']:
>>>     v1_ = walker1[p1]
>>>     print('*fail p1, v1, v2 = {}, {}, {}'.format(p1, v1, v2))
>>> for p1 in return_info['passlist']:
>>>     v1_ = walker1[p1]
>>>     print('*pass p1, v1_ = {}, {}'.format(p1, v1_))
>>> assert not flag

>>> import ubelt as ub
>>> dct1 = {
>>>     'foo': [1.0000000000000000000000001, 1.],
>>>     'bar': 1,
>>>     'baz': [],
>>> }
>>> dct2 = {
>>>     'foo': [0.9999999999999999, 1.],
>>>     'bar': 1,
>>>     'baz': [],
>>> }
>>> flag, return_info =  ub.indexable_allclose(dct1, dct2, return_info=True)
>>> print('return_info = {}'.format(ub.repr2(return_info, nl=1)))
>>> print('flag = {!r}'.format(flag))

Example

>>> import ubelt as ub
>>> flag, return_info =  ub.indexable_allclose([], [], return_info=True)
>>> print('return_info = {!r}'.format(return_info))
>>> print('flag = {!r}'.format(flag))

Example

>>> import ubelt as ub
>>> flag =  ub.indexable_allclose([], [], return_info=False)
>>> print('flag = {!r}'.format(flag))

Example

>>> import ubelt as ub
>>> flag, return_info =  ub.indexable_allclose([], [1], return_info=True)
>>> print('return_info = {!r}'.format(return_info))
>>> print('flag = {!r}'.format(flag))

ubelt.inject_method(self, func, name=None)

Injects a function into an object instance as a bound method

The main use case of this function is for monkey patching. While monkey patching is sometimes necessary it should generally be avoided. Thus, we simply remind the developer that there might be a better way.

Parameters

• self (T) – Instance to inject a function into.

• func (Callable[…, Any]) – The function to inject (must contain an arg for self).

• name (str, default=None) – Name of the method. optional. If not specified the name of the function is used.

Example

>>> import ubelt as ub
>>> class Foo(object):
>>>     def bar(self):
>>>         return 'bar'
>>> def baz(self):
>>>     return 'baz'
>>> self = Foo()
>>> assert self.bar() == 'bar'
>>> assert not hasattr(self, 'baz')
>>> ub.inject_method(self, baz)
>>> assert not hasattr(Foo, 'baz'), 'should only change one instance'
>>> assert self.baz() == 'baz'
>>> ub.inject_method(self, baz, 'bar')
>>> assert self.bar() == 'baz'

ubelt.invert_dict(dict_, unique_vals=True)

Swaps the keys and values in a dictionary.

Parameters

• dict_ (Dict[KT, VT]) – dictionary to invert

• unique_vals (bool, default=True) – if False, the values of the new dictionary are sets of the original keys.

Returns

the inverted dictionary

Return type

Dict[VT, KT] | Dict[VT, Set[KT]]

Note

The must values be hashable.

If the original dictionary contains duplicate values, then only one of the corresponding keys will be returned and the others will be discarded. This can be prevented by setting unique_vals=False, causing the inverted keys to be returned in a set.

Example

>>> import ubelt as ub
>>> dict_ = {'a': 1, 'b': 2}
>>> inverted = ub.invert_dict(dict_)
>>> assert inverted == {1: 'a', 2: 'b'}

Example

>>> import ubelt as ub
>>> dict_ = ub.odict([(2, 'a'), (1, 'b'), (0, 'c'), (None, 'd')])
>>> inverted = ub.invert_dict(dict_)
>>> assert list(inverted.keys())[0] == 'a'

Example

>>> import ubelt as ub
>>> dict_ = {'a': 1, 'b': 0, 'c': 0, 'd': 0, 'f': 2}
>>> inverted = ub.invert_dict(dict_, unique_vals=False)
>>> assert inverted == {0: {'b', 'c', 'd'}, 1: {'a'}, 2: {'f'}}

ubelt.iter_window(iterable, size=2, step=1, wrap=False)

Iterates through iterable with a window size. This is essentially a 1D sliding window.

Parameters

• iterable (Iterable[T]) – an iterable sequence

• size (int, default=2) – sliding window size

• step (int, default=1) – sliding step size

• wrap (bool, default=False) – wraparound flag

Returns

returns a possibly overlapping windows in a sequence

Return type

Iterable[T]

Notes

Similar to more_itertools.windowed(), Similar to more_itertools.pairwise(), Similar to more_itertools.triplewise(), Similar to more_itertools.sliding_window()

Example

>>> import ubelt as ub
>>> iterable = [1, 2, 3, 4, 5, 6]
>>> size, step, wrap = 3, 1, True
>>> window_iter = ub.iter_window(iterable, size, step, wrap)
>>> window_list = list(window_iter)
>>> print('window_list = %r' % (window_list,))
window_list = [(1, 2, 3), (2, 3, 4), (3, 4, 5), (4, 5, 6), (5, 6, 1), (6, 1, 2)]

Example

>>> import ubelt as ub
>>> iterable = [1, 2, 3, 4, 5, 6]
>>> size, step, wrap = 3, 2, True
>>> window_iter = ub.iter_window(iterable, size, step, wrap)
>>> window_list = list(window_iter)
>>> print('window_list = {!r}'.format(window_list))
window_list = [(1, 2, 3), (3, 4, 5), (5, 6, 1)]

Example

>>> import ubelt as ub
>>> iterable = [1, 2, 3, 4, 5, 6]
>>> size, step, wrap = 3, 2, False
>>> window_iter = ub.iter_window(iterable, size, step, wrap)
>>> window_list = list(window_iter)
>>> print('window_list = {!r}'.format(window_list))
window_list = [(1, 2, 3), (3, 4, 5)]

Example

>>> import ubelt as ub
>>> iterable = []
>>> size, step, wrap = 3, 2, False
>>> window_iter = ub.iter_window(iterable, size, step, wrap)
>>> window_list = list(window_iter)
>>> print('window_list = {!r}'.format(window_list))
window_list = []

ubelt.iterable(obj, strok=False)

Checks if the input implements the iterator interface. An exception is made for strings, which return False unless strok is True

Parameters

• obj (object) – a scalar or iterable input

• strok (bool, default=False) – if True allow strings to be interpreted as iterable

Returns

True if the input is iterable

Return type

bool

Example

>>> import ubelt as ub
>>> obj_list = [3, [3], '3', (3,), [3, 4, 5], {}]
>>> result = [ub.iterable(obj) for obj in obj_list]
>>> assert result == [False, True, False, True, True, True]
>>> result = [ub.iterable(obj, strok=True) for obj in obj_list]
>>> assert result == [False, True, True, True, True, True]

ubelt.map_keys(func, dict_)

Apply a function to every key in a dictionary.

Creates a new dictionary with the same values and modified keys. An error is raised if the new keys are not unique.

Parameters

• func (Callable[[KT], T] | Mapping[KT, T]) – a function or indexable object

• dict_ (Dict[KT, VT]) – a dictionary

Returns

transformed dictionary

Return type

Dict[T, VT]

Raises

Exception – if multiple keys map to the same value

Example

>>> import ubelt as ub
>>> dict_ = {'a': [1, 2, 3], 'b': []}
>>> func = ord
>>> newdict = ub.map_keys(func, dict_)
>>> print(newdict)
>>> assert newdict == {97: [1, 2, 3], 98: []}
>>> dict_ = {0: [1, 2, 3], 1: []}
>>> func = ['a', 'b']
>>> newdict = ub.map_keys(func, dict_)
>>> print(newdict)
>>> assert newdict == {'a': [1, 2, 3], 'b': []}

ubelt.map_vals(func, dict_)

Apply a function to every value in a dictionary.

Creates a new dictionary with the same keys and modified values.

Parameters

• func (Callable[[VT], T] | Mapping[VT, T]) – a function or indexable object

• dict_ (Dict[KT, VT]) – a dictionary

Returns

transformed dictionary

Return type

Dict[KT, T]

Example

>>> import ubelt as ub
>>> dict_ = {'a': [1, 2, 3], 'b': []}
>>> newdict = ub.map_vals(len, dict_)
>>> assert newdict ==  {'a': 3, 'b': 0}

Example

>>> # Can also use an indexable as ``func``
>>> import ubelt as ub
>>> dict_ = {'a': 0, 'b': 1}
>>> func = [42, 21]
>>> newdict = ub.map_vals(func, dict_)
>>> assert newdict ==  {'a': 42, 'b': 21}
>>> print(newdict)

ubelt.memoize(func)

memoization decorator that respects args and kwargs

Parameters

func (Callable) – live python function

Returns

memoized wrapper

Return type

Callable

References

WikiMemoize

https://wiki.python.org/moin/PythonDecoratorLibrary#Memoize

FunctoolsCache

https://docs.python.org/3/library/functools.html

Example

>>> import ubelt as ub
>>> closure = {'a': 'b', 'c': 'd'}
>>> incr = [0]
>>> def foo(key):
>>>     value = closure[key]
>>>     incr[0] += 1
>>>     return value
>>> foo_memo = ub.memoize(foo)
>>> assert foo('a') == 'b' and foo('c') == 'd'
>>> assert incr[0] == 2
>>> print('Call memoized version')
>>> assert foo_memo('a') == 'b' and foo_memo('c') == 'd'
>>> assert incr[0] == 4
>>> assert foo_memo('a') == 'b' and foo_memo('c') == 'd'
>>> print('Counter should no longer increase')
>>> assert incr[0] == 4
>>> print('Closure changes result without memoization')
>>> closure = {'a': 0, 'c': 1}
>>> assert foo('a') == 0 and foo('c') == 1
>>> assert incr[0] == 6
>>> assert foo_memo('a') == 'b' and foo_memo('c') == 'd'

class ubelt.memoize_method(func)

Bases: object

memoization decorator for a method that respects args and kwargs

References

ActiveState_Miller_2010

http://code.activestate.com/recipes/577452-a-memoize-decorator-for-instance-methods

Example

>>> import ubelt as ub
>>> closure = {'a': 'b', 'c': 'd'}
>>> incr = [0]
>>> class Foo(object):
>>>     @memoize_method
>>>     def foo_memo(self, key):
>>>         value = closure[key]
>>>         incr[0] += 1
>>>         return value
>>>     def foo(self, key):
>>>         value = closure[key]
>>>         incr[0] += 1
>>>         return value
>>> self = Foo()
>>> assert self.foo('a') == 'b' and self.foo('c') == 'd'
>>> assert incr[0] == 2
>>> print('Call memoized version')
>>> assert self.foo_memo('a') == 'b' and self.foo_memo('c') == 'd'
>>> assert incr[0] == 4
>>> assert self.foo_memo('a') == 'b' and self.foo_memo('c') == 'd'
>>> print('Counter should no longer increase')
>>> assert incr[0] == 4
>>> print('Closure changes result without memoization')
>>> closure = {'a': 0, 'c': 1}
>>> assert self.foo('a') == 0 and self.foo('c') == 1
>>> assert incr[0] == 6
>>> assert self.foo_memo('a') == 'b' and self.foo_memo('c') == 'd'
>>> print('Constructing a new object should get a new cache')
>>> self2 = Foo()
>>> self2.foo_memo('a')
>>> assert incr[0] == 7
>>> self2.foo_memo('a')
>>> assert incr[0] == 7

ubelt.memoize_property(fget)

Return a property attribute for new-style classes that only calls its getter on the first access. The result is stored and on subsequent accesses is returned, preventing the need to call the getter any more.

This decorator can either be used by itself or by decorating another property. In either case the method will always become a property.

Note

implementation is a modified version of [estebistec_memoize].

References

estebistec_memoize

https://github.com/estebistec/python-memoized-property

Example

>>> import ubelt as ub
>>> class C(object):
...     load_name_count = 0
...     @ub.memoize_property
...     def name(self):
...         "name's docstring"
...         self.load_name_count += 1
...         return "the name"
...     @ub.memoize_property
...     @property
...     def another_name(self):
...         "name's docstring"
...         self.load_name_count += 1
...         return "the name"
>>> c = C()
>>> c.load_name_count
0
>>> c.name
'the name'
>>> c.load_name_count
1
>>> c.name
'the name'
>>> c.load_name_count
1
>>> c.another_name

ubelt.modname_to_modpath(modname, hide_init=True, hide_main=False, sys_path=None)

Finds the path to a python module from its name.

Determines the path to a python module without directly import it

Converts the name of a module (__name__) to the path (__file__) where it is located without importing the module. Returns None if the module does not exist.

Parameters

• modname (str) – module filepath

• hide_init (bool) – if False, __init__.py will be returned for packages

• hide_main (bool) – if False, and hide_init is True, __main__.py will be returned for packages, if it exists.

• sys_path (list, default=None) – if specified overrides sys.path

Returns

modpath - path to the module, or None if it doesn’t exist

Return type

str

Example

>>> modname = 'xdoctest.__main__'
>>> modpath = modname_to_modpath(modname, hide_main=False)
>>> assert modpath.endswith('__main__.py')
>>> modname = 'xdoctest'
>>> modpath = modname_to_modpath(modname, hide_init=False)
>>> assert modpath.endswith('__init__.py')
>>> # xdoctest: +REQUIRES(CPython)
>>> modpath = basename(modname_to_modpath('_ctypes'))
>>> assert 'ctypes' in modpath

ubelt.modpath_to_modname(modpath, hide_init=True, hide_main=False, check=True, relativeto=None)

Determines importable name from file path

Converts the path to a module (__file__) to the importable python name (__name__) without importing the module.

The filename is converted to a module name, and parent directories are recursively included until a directory without an __init__.py file is encountered.

Parameters

• modpath (str) – module filepath

• hide_init (bool, default=True) – removes the __init__ suffix

• hide_main (bool, default=False) – removes the __main__ suffix

• check (bool, default=True) – if False, does not raise an error if modpath is a dir and does not contain an __init__ file.

• relativeto (str, default=None) – if specified, all checks are ignored and this is considered the path to the root module.

Todo

• [ ] Does this need modification to support PEP 420?

  https://www.python.org/dev/peps/pep-0420/

Returns

modname

Return type

str

Raises

ValueError – if check is True and the path does not exist

Example

>>> from xdoctest import static_analysis
>>> modpath = static_analysis.__file__.replace('.pyc', '.py')
>>> modpath = modpath.replace('.pyc', '.py')
>>> modname = modpath_to_modname(modpath)
>>> assert modname == 'xdoctest.static_analysis'

Example

>>> import xdoctest
>>> assert modpath_to_modname(xdoctest.__file__.replace('.pyc', '.py')) == 'xdoctest'
>>> assert modpath_to_modname(dirname(xdoctest.__file__.replace('.pyc', '.py'))) == 'xdoctest'

Example

>>> # xdoctest: +REQUIRES(CPython)
>>> modpath = modname_to_modpath('_ctypes')
>>> modname = modpath_to_modname(modpath)
>>> assert modname == '_ctypes'

Example

>>> modpath = '/foo/libfoobar.linux-x86_64-3.6.so'
>>> modname = modpath_to_modname(modpath, check=False)
>>> assert modname == 'libfoobar'

ubelt.named_product(_=None, **basis)

Generates the Cartesian product of the basis.values(), where each generated item labeled by basis.keys().

In other words, given a dictionary that maps each “axes” (i.e. some variable) to its “basis” (i.e. the possible values that it can take), generate all possible points in that grid (i.e. unique assignments of variables to values).

Parameters

• _ (Dict[str, List[VT]] | None, default=None) – Use of this positional argument is not recommend. Instead specify all arguments as keyword args.

  If specified, this should be a dictionary is unioned with the keyword args. This exists to support ordered dictionaries before Python 3.6, and may eventually be removed.

• basis (Dict[str, List[VT]]) – A dictionary where the keys correspond to “columns” and the values are a list of possible values that “column” can take.

  I.E. each key corresponds to an “axes”, the values are the list of possible values for that “axes”.

Yields

Dict[str, VT] – a “row” in the “longform” data containing a point in the Cartesian product.

Note

This function is similar to itertools.product(), the only difference is that the generated items are a dictionary that retains the input keys instead of an tuple.

This function used to be called “basis_product”, but “named_product” might be more appropriate. This function exists in other places ([minstrel271_namedproduct], [pytb_namedproduct], and [Hettinger_namedproduct]).

References

minstrel271_namedproduct

https://gist.github.com/minstrel271/d51654af3fa4e6411267

pytb_namedproduct

https://py-toolbox.readthedocs.io/en/latest/modules/itertools.html#

Hettinger_namedproduct

https://twitter.com/raymondh/status/970380630822305792

Example

>>> # An example use case is looping over all possible settings in a
>>> # configuration dictionary for a grid search over parameters.
>>> import ubelt as ub
>>> basis = {
>>>     'arg1': [1, 2, 3],
>>>     'arg2': ['A1', 'B1'],
>>>     'arg3': [9999, 'Z2'],
>>>     'arg4': ['always'],
>>> }
>>> import ubelt as ub
>>> # sort input data for older python versions
>>> basis = ub.odict(sorted(basis.items()))
>>> got = list(ub.named_product(basis))
>>> print(ub.repr2(got, nl=-1))
[
    {'arg1': 1, 'arg2': 'A1', 'arg3': 9999, 'arg4': 'always'},
    {'arg1': 1, 'arg2': 'A1', 'arg3': 'Z2', 'arg4': 'always'},
    {'arg1': 1, 'arg2': 'B1', 'arg3': 9999, 'arg4': 'always'},
    {'arg1': 1, 'arg2': 'B1', 'arg3': 'Z2', 'arg4': 'always'},
    {'arg1': 2, 'arg2': 'A1', 'arg3': 9999, 'arg4': 'always'},
    {'arg1': 2, 'arg2': 'A1', 'arg3': 'Z2', 'arg4': 'always'},
    {'arg1': 2, 'arg2': 'B1', 'arg3': 9999, 'arg4': 'always'},
    {'arg1': 2, 'arg2': 'B1', 'arg3': 'Z2', 'arg4': 'always'},
    {'arg1': 3, 'arg2': 'A1', 'arg3': 9999, 'arg4': 'always'},
    {'arg1': 3, 'arg2': 'A1', 'arg3': 'Z2', 'arg4': 'always'},
    {'arg1': 3, 'arg2': 'B1', 'arg3': 9999, 'arg4': 'always'},
    {'arg1': 3, 'arg2': 'B1', 'arg3': 'Z2', 'arg4': 'always'}
]

Example

>>> import ubelt as ub
>>> list(ub.named_product(a=[1, 2, 3]))
[{'a': 1}, {'a': 2}, {'a': 3}]
>>> # xdoctest: +IGNORE_WANT
>>> list(ub.named_product(a=[1, 2, 3], b=[4, 5]))
[{'a': 1, 'b': 4},
 {'a': 1, 'b': 5},
 {'a': 2, 'b': 4},
 {'a': 2, 'b': 5},
 {'a': 3, 'b': 4},
 {'a': 3, 'b': 5}]

ubelt.odict

alias of collections.OrderedDict

ubelt.oset

alias of ubelt.orderedset.OrderedSet

ubelt.paragraph(text)

Wraps multi-line strings and restructures the text to remove all newlines, heading, trailing, and double spaces.

Useful for writing log messages

Parameters

text (str) – typically a multiline string

Returns

the reduced text block

Return type

str

Example

>>> import ubelt as ub
>>> text = (
>>>     '''
>>>     Lorem ipsum dolor sit amet, consectetur adipiscing
>>>     elit, sed do eiusmod tempor incididunt ut labore et
>>>     dolore magna aliqua.
>>>     ''')
>>> out = ub.paragraph(text)
>>> assert chr(10) in text
>>> assert chr(10) not in out
>>> print('text = {!r}'.format(text))
>>> print('out = {!r}'.format(out))

ubelt.peek(iterable, default=NoParam)

Look at the first item of an iterable. If the input is an iterator, then the next element is exhausted (i.e. a pop operation).

Parameters

• iterable (Iterable[T]) – an iterable

• default (T) – default item to return if the iterable is empty, otherwise a StopIteration error is raised

Returns

item - the first item of ordered sequence, a popped item from an

iterator, or an arbitrary item from an unordered collection.

Return type

T

Notes

Similar to more_itertools.peekable()

Example

>>> import ubelt as ub
>>> data = [0, 1, 2]
>>> ub.peek(data)
0
>>> iterator = iter(data)
>>> print(ub.peek(iterator))
0
>>> print(ub.peek(iterator))
1
>>> print(ub.peek(iterator))
2
>>> ub.peek(range(3))
0
>>> ub.peek([], 3)
3

ubelt.platform_cache_dir()

Returns a directory which should be writable for any application This should be used for temporary deletable data.

Returns

path to the cache dir used by the current operating system

Return type

str

ubelt.platform_config_dir()

Returns a directory which should be writable for any application This should be used for persistent configuration files.

Returns

path to the cache dir used by the current operating system

Return type

str

ubelt.platform_data_dir()

Returns path for user-specific data files

Returns

path to the data dir used by the current operating system

Return type

str

ubelt.platform_resource_dir()

Alias for platform_cache_dir

DEPRECATED in favor of platform_config_dir / platform_data_dir

Returns a directory which should be writable for any application This should be used for persistent configuration files.

Returns

path to the resource dir used by the current operating system

Return type

PathLike

ubelt.readfrom(fpath, aslines=False, errors='replace', verbose=None)

Reads (utf8) text from a file.

Note

You probably should use open(<fpath>).read() instead. This function exists as a convenience for writing in Python2. After 2020-01-01, we may consider deprecating the function.

Parameters

• fpath (str | PathLike) – file path

• aslines (bool) – if True returns list of lines

• verbose (bool) – verbosity flag

Returns

text from fpath (this is unicode)

Return type

str

ubelt.repr2(data, **kwargs)

Makes a pretty string representation of data.

Makes a pretty and easy-to-doctest string representation. Has nice handling of common nested datatypes. This is an alternative to repr, and pprint.pformat().

This output of this function are configurable. By default it aims to produce strings that are consistent, compact, and executable. This makes them great for doctests.

Note

This function has many keyword arguments that can be used to customize the final representation. For convenience some of the more frequently used kwargs have short aliases. See “Kwargs” for more details.

Parameters

data (object) – an arbitrary python object to form the string “representation” of

Kwargs:

si, stritems, (bool):

dict/list items use str instead of repr

strkeys, sk (bool):

dict keys use str instead of repr

strvals, sv (bool):

dict values use str instead of repr

nl, newlines (int | bool):

number of top level nestings to place a newline after. If true all items are followed by newlines regardless of nesting level. Defaults to 1 for lists and True for dicts.

nobr, nobraces (bool, default=False):

if True, text will not contain outer braces for containers

cbr, compact_brace (bool, default=False):

if True, braces are compactified (i.e. they will not have newlines placed directly after them, think java / K&R / 1TBS)

trailsep, trailing_sep (bool):

if True, a separator is placed after the last item in a sequence. By default this is True if there are any nl > 0.

explicit (bool, default=False):

changes dict representation from {k1: v1, ...} to dict(k1=v1, ...).

Modifies:

default kvsep is modified to '=' dict braces from {} to dict().

compact (bool, default=False):

Produces values more suitable for space constrianed environments

Modifies:

default kvsep is modified to '=' default itemsep is modified to '' default nobraces is modified to 1. default nl is modified to 0. default strkeys to True default strvals to True

precision (int, default=None):

if specified floats are formatted with this precision

kvsep (str, default=’: ‘):

separator between keys and values

itemsep (str, default=’ ‘):

separator between items

sort (bool | callable, default=None):

if None, then sort unordered collections, but keep the ordering of ordered collections. This option attempts to be deterministic in most cases.

New in 0.8.0: if sort is callable, it will be used as a key-function to sort all collections.

if False, then nothing will be sorted, and the representation of unordered collections will be arbitrary and possibly non-determenistic.

if True, attempts to sort all collections in the returned text. Currently if True this WILL sort lists. Currently if True this WILL NOT sort OrderedDicts.

NOTE:

The previous behavior may not be intuitive, as such the behavior of this arg is subject to change.

suppress_small (bool):

passed to numpy.array2string() for ndarrays

max_line_width (int):

passed to numpy.array2string() for ndarrays

with_dtype (bool):

only relevant to numpy.ndarrays. if True includes the dtype. Defaults to not strvals.

align (bool | str, default=False):

if True, will align multi-line dictionaries by the kvsep

extensions (FormatterExtensions):

a custom FormatterExtensions instance that can overwrite or define how different types of objects are formatted.

Returns

outstr - output string

Return type

str

Note

There are also internal kwargs, which should not be used:

_return_info (bool): return information about child context

_root_info (depth): information about parent context

RelatedWork:

rich.pretty.pretty_repr() pprint.pformat()

Example

>>> import ubelt as ub
>>> dict_ = {
...     'custom_types': [slice(0, 1, None), 1/3],
...     'nest_dict': {'k1': [1, 2, {3: {4, 5}}],
...                   'key2': [1, 2, {3: {4, 5}}],
...                   'key3': [1, 2, {3: {4, 5}}],
...                   },
...     'nest_dict2': {'k': [1, 2, {3: {4, 5}}]},
...     'nested_tuples': [tuple([1]), tuple([2, 3]), frozenset([4, 5, 6])],
...     'one_tup': tuple([1]),
...     'simple_dict': {'spam': 'eggs', 'ham': 'jam'},
...     'simple_list': [1, 2, 'red', 'blue'],
...     'odict': ub.odict([(1, '1'), (2, '2')]),
... }
>>> # In the interest of saving space we are only going to show the
>>> # output for the first example.
>>> result = ub.repr2(dict_, nl=1, precision=2)
>>> print(result)
{
    'custom_types': [slice(0, 1, None), 0.33],
    'nest_dict': {'k1': [1, 2, {3: {4, 5}}], 'key2': [1, 2, {3: {4, 5}}], 'key3': [1, 2, {3: {4, 5}}]},
    'nest_dict2': {'k': [1, 2, {3: {4, 5}}]},
    'nested_tuples': [(1,), (2, 3), {4, 5, 6}],
    'odict': {1: '1', 2: '2'},
    'one_tup': (1,),
    'simple_dict': {'ham': 'jam', 'spam': 'eggs'},
    'simple_list': [1, 2, 'red', 'blue'],
}
>>> # You can try the rest yourself.
>>> result = ub.repr2(dict_, nl=3, precision=2); print(result)
>>> result = ub.repr2(dict_, nl=2, precision=2); print(result)
>>> result = ub.repr2(dict_, nl=1, precision=2, itemsep='', explicit=True); print(result)
>>> result = ub.repr2(dict_, nl=1, precision=2, nobr=1, itemsep='', explicit=True); print(result)
>>> result = ub.repr2(dict_, nl=3, precision=2, cbr=True); print(result)
>>> result = ub.repr2(dict_, nl=3, precision=2, si=True); print(result)
>>> result = ub.repr2(dict_, nl=3, sort=True); print(result)
>>> result = ub.repr2(dict_, nl=3, sort=False, trailing_sep=False); print(result)
>>> result = ub.repr2(dict_, nl=3, sort=False, trailing_sep=False, nobr=True); print(result)

Example

>>> import ubelt as ub
>>> def _nest(d, w):
...     if d == 0:
...         return {}
...     else:
...         return {'n{}'.format(d): _nest(d - 1, w + 1), 'm{}'.format(d): _nest(d - 1, w + 1)}
>>> dict_ = _nest(d=4, w=1)
>>> result = ub.repr2(dict_, nl=6, precision=2, cbr=1)
>>> print('---')
>>> print(result)
>>> result = ub.repr2(dict_, nl=-1, precision=2)
>>> print('---')
>>> print(result)

Example

>>> import ubelt as ub
>>> data = {'a': 100, 'b': [1, '2', 3], 'c': {20:30, 40: 'five'}}
>>> print(ub.repr2(data, nl=1))
{
    'a': 100,
    'b': [1, '2', 3],
    'c': {20: 30, 40: 'five'},
}
>>> # Compact is useful for things like timerit.Timerit labels
>>> print(ub.repr2(data, compact=True))
a=100,b=[1,2,3],c={20=30,40=five}
>>> print(ub.repr2(data, compact=True, nobr=False))
{a=100,b=[1,2,3],c={20=30,40=five}}

ubelt.schedule_deprecation(deprecate=None, error=None, remove=None)

Deprecation machinery to help provide users with a smoother transition

ubelt.shrinkuser(path, home='~')

Inverse of os.path.expanduser().

Parameters

• path (str | PathLike) – path in system file structure

• home (str, default=’~’) – symbol used to replace the home path. Defaults to ‘~’, but you might want to use ‘$HOME’ or ‘%USERPROFILE%’ instead.

Returns

path - shortened path replacing the home directory with a symbol

Return type

str

Example

>>> from ubelt.util_path import *  # NOQA
>>> path = expanduser('~')
>>> assert path != '~'
>>> assert shrinkuser(path) == '~'
>>> assert shrinkuser(path + '1') == path + '1'
>>> assert shrinkuser(path + '/1') == join('~', '1')
>>> assert shrinkuser(path + '/1', '$HOME') == join('$HOME', '1')
>>> assert shrinkuser('.') == '.'

ubelt.sorted_keys(dict_, key=None, reverse=False)

Return an ordered dictionary sorted by its keys

Parameters

• dict_ (Dict[KT, VT]) – dictionary to sort. The keys must be of comparable types.

• key (Callable[[KT], Any] | None) – If given as a callable, customizes the sorting by ordering using transformed keys.

• reverse (bool, default=False) – if True returns in descending order

Returns

new dictionary where the keys are ordered

Return type

OrderedDict[KT, VT]

Example

>>> import ubelt as ub
>>> dict_ = {'spam': 2.62, 'eggs': 1.20, 'jam': 2.92}
>>> newdict = sorted_keys(dict_)
>>> print(ub.repr2(newdict, nl=0))
{'eggs': 1.2, 'jam': 2.92, 'spam': 2.62}
>>> newdict = sorted_keys(dict_, reverse=True)
>>> print(ub.repr2(newdict, nl=0))
{'spam': 2.62, 'jam': 2.92, 'eggs': 1.2}
>>> newdict = sorted_keys(dict_, key=lambda x: sum(map(ord, x)))
>>> print(ub.repr2(newdict, nl=0))
{'jam': 2.92, 'eggs': 1.2, 'spam': 2.62}

ubelt.sorted_vals(dict_, key=None, reverse=False)

Return an ordered dictionary sorted by its values

Parameters

• dict_ (Dict[KT, VT]) – dictionary to sort. The values must be of comparable types.

• key (Callable[[VT], Any] | None) – If given as a callable, customizes the sorting by ordering using transformed values.

• reverse (bool, default=False) – if True returns in descending order

Returns

new dictionary where the values are ordered

Return type

OrderedDict[KT, VT]

Example

>>> import ubelt as ub
>>> dict_ = {'spam': 2.62, 'eggs': 1.20, 'jam': 2.92}
>>> newdict = sorted_vals(dict_)
>>> print(ub.repr2(newdict, nl=0))
{'eggs': 1.2, 'spam': 2.62, 'jam': 2.92}
>>> newdict = sorted_vals(dict_, reverse=True)
>>> print(ub.repr2(newdict, nl=0))
{'jam': 2.92, 'spam': 2.62, 'eggs': 1.2}
>>> newdict = sorted_vals(dict_, key=lambda x: x % 1.6)
>>> print(ub.repr2(newdict, nl=0))
{'spam': 2.62, 'eggs': 1.2, 'jam': 2.92}

ubelt.split_archive(fpath, ext='.zip')

If fpath specifies a file inside a zipfile, it breaks it into two parts the path to the zipfile and the internal path in the zipfile.

Example

>>> split_archive('/a/b/foo.txt')
>>> split_archive('/a/b/foo.zip/bar.txt')
>>> split_archive('/a/b/foo.zip/baz/biz.zip/bar.py')
>>> split_archive('archive.zip')
>>> import ubelt as ub
>>> split_archive(ub.Path('/a/b/foo.zip/baz/biz.zip/bar.py'))
>>> split_archive('/a/b/foo.zip/baz.pt/bar.zip/bar.zip', '.pt')

Todo

Fix got/want for win32

(None, None) (‘/a/b/foo.zip’, ‘bar.txt’) (‘/a/b/foo.zip/baz/biz.zip’, ‘bar.py’) (‘archive.zip’, None) (‘/a/b/foo.zip/baz/biz.zip’, ‘bar.py’) (‘/a/b/foo.zip/baz.pt’, ‘bar.zip/bar.zip’)

ubelt.split_modpath(modpath, check=True)

Splits the modpath into the dir that must be in PYTHONPATH for the module to be imported and the modulepath relative to this directory.

Parameters

• modpath (str) – module filepath

• check (bool) – if False, does not raise an error if modpath is a directory and does not contain an __init__.py file.

Returns

(directory, rel_modpath)

Return type

Tuple[str, str]

Raises

ValueError – if modpath does not exist or is not a package

Example

>>> from xdoctest import static_analysis
>>> modpath = static_analysis.__file__.replace('.pyc', '.py')
>>> modpath = abspath(modpath)
>>> dpath, rel_modpath = split_modpath(modpath)
>>> recon = join(dpath, rel_modpath)
>>> assert recon == modpath
>>> assert rel_modpath == join('xdoctest', 'static_analysis.py')

ubelt.startfile(fpath, verbose=True)

Uses default program defined by the system to open a file. This is done via os.startfile on windows, open on mac, and xdg-open on linux.

Parameters

• fpath (str | PathLike) – a file to open using the program associated with the files extension type.

• verbose (int) – verbosity

References

http://stackoverflow.com/questions/2692873/quote-posix

Example

>>> # xdoctest: +SKIP
>>> # This test interacts with a GUI frontend, not sure how to test.
>>> import ubelt as ub
>>> base = ub.ensure_app_cache_dir('ubelt')
>>> fpath1 = join(base, 'test_open.txt')
>>> ub.touch(fpath1)
>>> proc = ub.startfile(fpath1)

ubelt.symlink(real_path, link_path, overwrite=False, verbose=0)

Create a symbolic link.

This will work on linux or windows, however windows does have some corner cases. For more details see notes in ubelt._win32_links.

Parameters

• path (str | PathLike) – path to real file or directory

• link_path (str | PathLike) – path to desired location for symlink

• overwrite (bool, default=False) – overwrite existing symlinks. This will not overwrite real files on systems with proper symlinks. However, on older versions of windows junctions are indistinguishable from real files, so we cannot make this guarantee.

• verbose (int, default=0) – verbosity level

Returns

link path

Return type

str | PathLike

Example

>>> import ubelt as ub
>>> dpath = ub.ensure_app_cache_dir('ubelt', 'test_symlink0')
>>> real_path = join(dpath, 'real_file.txt')
>>> link_path = join(dpath, 'link_file.txt')
>>> [ub.delete(p) for p in [real_path, link_path]]
>>> ub.writeto(real_path, 'foo')
>>> result = symlink(real_path, link_path)
>>> assert ub.readfrom(result) == 'foo'
>>> [ub.delete(p) for p in [real_path, link_path]]

Example

>>> import ubelt as ub
>>> from os.path import dirname
>>> dpath = ub.ensure_app_cache_dir('ubelt', 'test_symlink1')
>>> ub.delete(dpath)
>>> ub.ensuredir(dpath)
>>> _dirstats(dpath)
>>> real_dpath = ub.ensuredir((dpath, 'real_dpath'))
>>> link_dpath = ub.augpath(real_dpath, base='link_dpath')
>>> real_path = join(dpath, 'afile.txt')
>>> link_path = join(dpath, 'afile.txt')
>>> [ub.delete(p) for p in [real_path, link_path]]
>>> ub.writeto(real_path, 'foo')
>>> result = symlink(real_dpath, link_dpath)
>>> assert ub.readfrom(link_path) == 'foo', 'read should be same'
>>> ub.writeto(link_path, 'bar')
>>> _dirstats(dpath)
>>> assert ub.readfrom(link_path) == 'bar', 'very bad bar'
>>> assert ub.readfrom(real_path) == 'bar', 'changing link did not change real'
>>> ub.writeto(real_path, 'baz')
>>> _dirstats(dpath)
>>> assert ub.readfrom(real_path) == 'baz', 'very bad baz'
>>> assert ub.readfrom(link_path) == 'baz', 'changing real did not change link'
>>> ub.delete(link_dpath, verbose=1)
>>> _dirstats(dpath)
>>> assert not exists(link_dpath), 'link should not exist'
>>> assert exists(real_path), 'real path should exist'
>>> _dirstats(dpath)
>>> ub.delete(dpath, verbose=1)
>>> _dirstats(dpath)
>>> assert not exists(real_path)

ubelt.take(items, indices, default=NoParam)

Lookup a subset of an indexable object using a sequence of indices.

The items input is usually a list or dictionary. When items is a list, this should be a sequence of integers. When items is a dict, this is a list of keys to lookup in that dictionary.

For dictionaries, a default may be specified as a placeholder to use if a key from indices is not in items.

Parameters

• items (Sequence[VT] | Mapping[KT, VT]) – An indexable object to select items from.

• indices (Iterable[int | KT]) – A sequence of indexes into items.

• default (Any, default=NoParam) – if specified items must support the get method.

Yields

VT – a selected item within the list

SeeAlso:

ubelt.dict_subset()

Note

ub.take(items, indices) is equivalent to (items[i] for i in indices) when default is unspecified.

Notes

This is based on the numpy.take() function, but written in pure python.

Do not confuse this with more_itertools.take(), the behavior is very different.

Example

>>> import ubelt as ub
>>> items = [0, 1, 2, 3]
>>> indices = [2, 0]
>>> list(ub.take(items, indices))
[2, 0]

Example

>>> import ubelt as ub
>>> dict_ = {1: 'a', 2: 'b', 3: 'c'}
>>> keys = [1, 2, 3, 4, 5]
>>> result = list(ub.take(dict_, keys, None))
>>> assert result == ['a', 'b', 'c', None, None]

Example

>>> import ubelt as ub
>>> dict_ = {1: 'a', 2: 'b', 3: 'c'}
>>> keys = [1, 2, 3, 4, 5]
>>> try:
>>>     print(list(ub.take(dict_, keys)))
>>>     raise AssertionError('did not get key error')
>>> except KeyError:
>>>     print('correctly got key error')

ubelt.timestamp(method='iso8601')

Make an iso8601 timestamp suitable for use in filenames

Parameters

method (str, default=’iso8601’) – type of timestamp

Returns

stamp

Return type

str

Example

>>> import ubelt as ub
>>> stamp = ub.timestamp()
>>> print('stamp = {!r}'.format(stamp))
stamp = ...-...-...T...

ubelt.touch(fpath, mode=438, dir_fd=None, verbose=0, **kwargs)

change file timestamps

Works like the touch unix utility

Parameters

• fpath (str | PathLike) – name of the file

• mode (int) – file permissions (python3 and unix only)

• dir_fd (io.IOBase) – optional directory file descriptor. If specified, fpath is interpreted as relative to this descriptor (python 3 only).

• verbose (int) – verbosity

• **kwargs – extra args passed to os.utime() (python 3 only).

Returns

path to the file

Return type

str

References

SO_1158076

https://stackoverflow.com/questions/1158076/implement-touch-using-python

Example

>>> import ubelt as ub
>>> from os.path import join
>>> dpath = ub.ensure_app_cache_dir('ubelt')
>>> fpath = join(dpath, 'touch_file')
>>> assert not exists(fpath)
>>> ub.touch(fpath)
>>> assert exists(fpath)
>>> os.unlink(fpath)

ubelt.truepath(path, real=False)

Normalizes a string representation of a path and does shell-like expansion.

Parameters

• path (str | PathLike) – string representation of a path

• real (bool) – if True, all symbolic links are followed. (default: False)

Returns

normalized path

Return type

str

Note

This function is similar to the composition of expanduser, expandvars, normpath, and (realpath if real else abspath). However, on windows backslashes are then replaced with forward slashes to offer a consistent unix-like experience across platforms.

On windows expanduser will expand environment variables formatted as %name%, whereas on unix, this will not occur.

Example

>>> from os.path import join
>>> import ubelt as ub
>>> assert ub.truepath('~/foo') == join(ub.userhome(), 'foo')
>>> assert ub.truepath('~/foo') == ub.truepath('~/foo/bar/..')
>>> assert ub.truepath('~/foo', real=True) == ub.truepath('~/foo')

ubelt.unique(items, key=None)

Generates unique items in the order they appear.

Parameters

• items (Iterable[T]) – list of items

• key (Callable[[T], Any], default=None) – custom normalization function. If specified returns items where key(item) is unique.

Yields

T – a unique item from the input sequence

Notes

Functionally equivalent to more_itertools.unique_everseen().

Example

>>> import ubelt as ub
>>> items = [4, 6, 6, 0, 6, 1, 0, 2, 2, 1]
>>> unique_items = list(ub.unique(items))
>>> assert unique_items == [4, 6, 0, 1, 2]

Example

>>> import ubelt as ub
>>> import six
>>> items = ['A', 'a', 'b', 'B', 'C', 'c', 'D', 'e', 'D', 'E']
>>> unique_items = list(ub.unique(items, key=six.text_type.lower))
>>> assert unique_items == ['A', 'b', 'C', 'D', 'e']
>>> unique_items = list(ub.unique(items))
>>> assert unique_items == ['A', 'a', 'b', 'B', 'C', 'c', 'D', 'e', 'E']

ubelt.unique_flags(items, key=None)

Returns a list of booleans corresponding to the first instance of each unique item.

Parameters

• items (Sequence[VT]) – indexable collection of items

• key (Callable[[VT], Any] | None, default=None) – custom normalization function. If specified returns items where key(item) is unique.

Returns

flags the items that are unique

Return type

List[bool]

Example

>>> import ubelt as ub
>>> items = [0, 2, 1, 1, 0, 9, 2]
>>> flags = ub.unique_flags(items)
>>> assert flags == [True, True, True, False, False, True, False]
>>> flags = ub.unique_flags(items, key=lambda x: x % 2 == 0)
>>> assert flags == [True, False, True, False, False, False, False]

ubelt.userhome(username=None)

Returns the path to some user’s home directory.

Parameters

username (str | None, default=None) – name of a user on the system. If not specified, the current user is inferred.

Returns

userhome_dpath - path to the specified home directory

Return type

str

Raises

• KeyError – if the specified user does not exist on the system

• OSError – if username is unspecified and the current user cannot be inferred

Example

>>> from ubelt.util_path import *  # NOQA
>>> import getpass
>>> username = getpass.getuser()
>>> assert userhome() == expanduser('~')
>>> assert userhome(username) == expanduser('~')

ubelt.varied_values(longform, min_variations=0, default=NoParam)

Given a list of dictionaries, find the values that differ between them.

Parameters

• longform (List[Dict[KT, VT]]) – This is longform data, as described in [SeabornLongform]. It is a list of dictionaries.

  Each item in the list - or row - is a dictionary and can be thought of as an observation. The keys in each dictionary are the columns. The values of the dictionary must be hashable. Lists will be converted into tuples.

• min_variations (int, default=0) – “columns” with fewer than min_variations unique values are removed from the result.

• default (VT, default=NoParam) – if specified, unspecified columns are given this value.

Returns

a mapping from each “column” to the set of unique values it took over each “row”. If a column is not specified for each row, it is assumed to take a default value, if it is specified.

Return type

Dict[KT, List[VT]]

Raises

KeyError – If default is unspecified and all the rows do not contain the same columns.

References

SeabornLongform

https://seaborn.pydata.org/tutorial/data_structure.html#long-form-data

Example

>>> # An example use case is to determine what values of a
>>> # configuration dictionary were tried in a random search
>>> # over a parameter grid.
>>> import ubelt as ub
>>> longform = [
>>>     {'col1': 1, 'col2': 'foo', 'col3': None},
>>>     {'col1': 1, 'col2': 'foo', 'col3': None},
>>>     {'col1': 2, 'col2': 'bar', 'col3': None},
>>>     {'col1': 3, 'col2': 'bar', 'col3': None},
>>>     {'col1': 9, 'col2': 'bar', 'col3': None},
>>>     {'col1': 1, 'col2': 'bar', 'col3': None},
>>> ]
>>> varied = ub.varied_values(longform)
>>> print('varied = {}'.format(ub.repr2(varied, nl=1)))
varied = {
    'col1': {1, 2, 3, 9},
    'col2': {'bar', 'foo'},
    'col3': {None},
}

Example

>>> import ubelt as ub
>>> import random
>>> longform = [
>>>     {'col1': 1, 'col2': 'foo', 'col3': None},
>>>     {'col1': 1, 'col2': [1, 2], 'col3': None},
>>>     {'col1': 2, 'col2': 'bar', 'col3': None},
>>>     {'col1': 3, 'col2': 'bar', 'col3': None},
>>>     {'col1': 9, 'col2': 'bar', 'col3': None},
>>>     {'col1': 1, 'col2': 'bar', 'col3': None, 'extra_col': 3},
>>> ]
>>> # Operation fails without a default
>>> import pytest
>>> with pytest.raises(KeyError):
>>>     varied = ub.varied_values(longform)
>>> #
>>> # Operation works with a default
>>> varied = ub.varied_values(longform, default='<unset>')
>>> expected = {
>>>     'col1': {1, 2, 3, 9},
>>>     'col2': {'bar', 'foo', (1, 2)},
>>>     'col3': set([None]),
>>>     'extra_col': {'<unset>', 3},
>>> }
>>> print('varied = {!r}'.format(varied))
>>> assert varied == expected

Example

>>> # xdoctest: +REQUIRES(PY3)
>>> # Random numbers are different in Python2, so skip in that case
>>> import ubelt as ub
>>> import random
>>> num_cols = 11
>>> num_rows = 17
>>> rng = random.Random(0)
>>> # Generate a set of columns
>>> columns = sorted(ub.hash_data(i)[0:8] for i in range(num_cols))
>>> # Generate rows for each column
>>> longform = [
>>>     {key: ub.hash_data(key)[0:8] for key in columns}
>>>     for _ in range(num_rows)
>>> ]
>>> # Add in some varied values in random positions
>>> for row in longform:
>>>     if rng.random() > 0.5:
>>>         for key in sorted(row.keys()):
>>>             if rng.random() > 0.95:
>>>                 row[key] = 'special-' + str(rng.randint(1, 32))
>>> varied = ub.varied_values(longform, min_variations=1)
>>> print('varied = {}'.format(ub.repr2(varied, nl=1, sort=True)))
varied = {
    '095f3e44': {'8fb4d4c9', 'special-23'},
    '365d11a1': {'daa409da', 'special-31', 'special-32'},
    '5815087d': {'1b823610', 'special-3'},
    '7b54b668': {'349a782c', 'special-10'},
    'b8244d02': {'d57bca90', 'special-8'},
    'f27b5bf8': {'fa0f90d1', 'special-19'},
}

ubelt.writeto(fpath, to_write, aslines=False, verbose=None)

Writes (utf8) text to a file.

Parameters

• fpath (str | PathLike) – file path

• to_write (str) – text to write (must be unicode text)

• aslines (bool) – if True to_write is assumed to be a list of lines

• verbose (bool) – verbosity flag

Note

In CPython you may want to use open(<fpath>).write(<to_write>) instead. This function exists as a convenience for writing in Python2. After 2020-01-01, we may consider deprecating the function.

NOTE: In PyPy open(<fpath>).write(<to_write>) does not work. See https://pypy.org/compat.html. This is a strong argument for keeping this function.

Example

>>> import ubelt as ub
>>> dpath = ub.ensure_app_cache_dir('ubelt')
>>> fpath = dpath + '/' + 'testwrite.txt'
>>> if exists(fpath):
>>>     os.remove(fpath)
>>> to_write = 'utf-8 symbols Δ, Й, ק, م, ๗, あ, 叶, 葉, and 말.'
>>> writeto(fpath, to_write)
>>> read_ = ub.readfrom(fpath)
>>> print('read_    = ' + read_)
>>> print('to_write = ' + to_write)
>>> assert read_ == to_write

Example

>>> import ubelt as ub
>>> dpath = ub.ensure_app_cache_dir('ubelt')
>>> fpath = dpath + '/' + 'testwrite2.txt'
>>> if exists(fpath):
>>>     os.remove(fpath)
>>> to_write = ['a\n', 'b\n', 'c\n', 'd\n']
>>> writeto(fpath, to_write, aslines=True)
>>> read_ = ub.readfrom(fpath, aslines=True)
>>> print('read_    = {}'.format(read_))
>>> print('to_write = {}'.format(to_write))
>>> assert read_ == to_write

class ubelt.zopen(fpath, mode='r', seekable=False, ext='.zip')

Bases: ubelt.util_mixins.NiceRepr

An abstraction of the normal open() function that can also handle reading data directly inside of zipfiles.

This is a file-object like interface [FileObj] — i.e. it supports the read and write methods to an underlying resource.

Can open a file normally or open a file within a zip file (readonly). Tries to read from memory only, but will extract to a tempfile if necessary.

Just treat the zipfile like a directory, e.g. /path/to/myzip.zip/compressed/path.txt OR? e.g. /path/to/myzip.zip:compressed/path.txt

References

FileObj

https://docs.python.org/3/glossary.html#term-file-object

Todo

• [ ] Fast way to open a base zipfile, query what is inside, and

  then choose a file to further zopen (and passing along the same open zipfile reference maybe?).

• [ ] Write mode in some restricted setting?

Parameters

• fpath (str | PathLike) – path to a file, or a special path that denotes both a path to a zipfile and a path to a archived file inside of the zipfile.

• mode (str) – Currently only “r” - readonly mode is supported

• seekable (bool) – If True, attempts to force “seekability” of the underlying file-object, for compressed files this will first extract the file to a temporary location on disk. If False, any underlying compressed file will be opened directly which may result in the object being non-seekable.

• ext (str) – The extension of the zipfile. Modify this is a non-standard extension is used (e.g. for torch packages).

Example

>>> from ubelt.util_zip import *  # NOQA
>>> import pickle
>>> import ubelt as ub
>>> dpath = ub.ensure_app_cache_dir('ubelt/tests/util_zip')
>>> dpath = ub.Path(dpath)
>>> data_fpath = dpath / 'test.pkl'
>>> data = {'demo': 'data'}
>>> with open(str(data_fpath), 'wb') as file:
>>>     pickle.dump(data, file)
>>> # Write data
>>> import zipfile
>>> zip_fpath = dpath / 'test_zip.archive'
>>> stl_w_zfile = zipfile.ZipFile(_fspath(zip_fpath), mode='w')
>>> stl_w_zfile.write(_fspath(data_fpath), _fspath(data_fpath.relative_to(dpath)))
>>> stl_w_zfile.close()
>>> stl_r_zfile = zipfile.ZipFile(_fspath(zip_fpath), mode='r')
>>> stl_r_zfile.namelist()
>>> stl_r_zfile.close()
>>> # Test zopen
>>> self = zopen(zip_fpath / 'test.pkl', mode='rb', ext='.archive')
>>> print(self._split_archive())
>>> print(self.namelist())
>>> self.close()
>>> self = zopen(zip_fpath / 'test.pkl', mode='rb', ext='.archive')
>>> recon1 = pickle.loads(self.read())
>>> self.close()
>>> self = zopen(zip_fpath / 'test.pkl', mode='rb', ext='.archive')
>>> recon2 = pickle.load(self)
>>> self.close()
>>> assert recon1 == recon2
>>> assert recon1 is not recon2

Example

>>> # Test we can load json data from a zipfile
>>> from ubelt.util_zip import *  # NOQA
>>> import ubelt as ub
>>> import json
>>> dpath = ub.ensure_app_cache_dir('ubelt/tests/util_zip')
>>> infopath = join(dpath, 'info.json')
>>> ub.writeto(infopath, '{"x": "1"}')
>>> zippath = join(dpath, 'infozip.zip')
>>> internal = 'folder/info.json'
>>> with zipfile.ZipFile(zippath, 'w') as myzip:
>>>     myzip.write(infopath, internal)
>>> fpath = zippath + '/' + internal
>>> # Test context manager
>>> with zopen(fpath, 'r') as self:
>>>     info2 = json.load(self)
>>>     assert info2['x'] == '1'
>>> # Test outside of context manager
>>> self = zopen(fpath, 'r')
>>> print(self._split_archive())
>>> info2 = json.load(self)
>>> assert info2['x'] == '1'
>>> # Test nice repr (with zfile)
>>> print('self = {!r}'.format(self))
>>> self.close()

Example

>>> # Coverage tests --- move to unit-test
>>> from ubelt.util_zip import *  # NOQA
>>> import ubelt as ub
>>> import json
>>> dpath = ub.ensure_app_cache_dir('ubelt/tests/util_zip')
>>> textpath = join(dpath, 'seekable_test.txt')
>>> text = chr(10).join(['line{}'.format(i) for i in range(10)])
>>> ub.writeto(textpath, text)
>>> zippath = join(dpath, 'seekable_test.zip')
>>> internal = 'folder/seekable_test.txt'
>>> with zipfile.ZipFile(zippath, 'w') as myzip:
>>>     myzip.write(textpath, internal)
>>> ub.delete(textpath)
>>> fpath = zippath + '/' + internal
>>> # Test seekable
>>> self_seekable = zopen(fpath, 'r', seekable=True)
>>> if not PY2:
>>>     assert self_seekable.seekable()
>>> self_seekable.seek(8)
>>> assert self_seekable.readline() == 'ne1' + chr(10)
>>> assert self_seekable.readline() == 'line2' + chr(10)
>>> self_seekable.seek(8)
>>> assert self_seekable.readline() == 'ne1' + chr(10)
>>> assert self_seekable.readline() == 'line2' + chr(10)
>>> # Test non-seekable?
>>> # Sometimes non-seekable files are still seekable
>>> maybe_seekable = zopen(fpath, 'r', seekable=False)
>>> print('PY2 = {!r}'.format(PY2))
>>> if not PY2 and maybe_seekable.seekable():
>>>     maybe_seekable.seek(8)
>>>     assert maybe_seekable.readline() == 'ne1' + chr(10)
>>>     assert maybe_seekable.readline() == 'line2' + chr(10)
>>>     maybe_seekable.seek(8)
>>>     assert maybe_seekable.readline() == 'ne1' + chr(10)
>>>     assert maybe_seekable.readline() == 'line2' + chr(10)

Example

>>> # More coverage tests --- move to unit-test
>>> from ubelt.util_zip import *  # NOQA
>>> import ubelt as ub
>>> import pytest
>>> dpath = ub.ensure_app_cache_dir('ubelt/tests/util_zip')
>>> with pytest.raises(OSError):
>>>     self = zopen('', 'r')
>>> # Test open non-zip exsting file
>>> existing_fpath = join(dpath, 'exists.json')
>>> ub.writeto(existing_fpath, '{"x": "1"}')
>>> self = zopen(existing_fpath, 'r')
>>> assert self.read() == '{"x": "1"}'
>>> # Test dir
>>> dir(self)
>>> # Test nice
>>> print(self)
>>> print('self = {!r}'.format(self))
>>> self.close()
>>> # Test open non-zip non-existing file
>>> nonexisting_fpath = join(dpath, 'does-not-exist.txt')
>>> ub.delete(nonexisting_fpath)
>>> with pytest.raises(OSError):
>>>     self = zopen(nonexisting_fpath, 'r')
>>> with pytest.raises(NotImplementedError):
>>>     self = zopen(nonexisting_fpath, 'w')
>>> # Test nice-repr
>>> self = zopen(existing_fpath, 'r')
>>> print('self = {!r}'.format(self))
>>> # pathological
>>> self = zopen(existing_fpath, 'r')
>>> self._handle = None
>>> dir(self)

property zfile

Access the underlying archive file

namelist()

Lists the contents of this zipfile