Source code for ubelt.progiter

# -*- coding: utf-8 -*-
"""
ProgIter IS BACK! It is at an almost-drop in replacement for TQDM, it is better
in some ways --- namely its simpler.

A Progress Iterator:

    The API is compatible with TQDM!

    We have our own ways of running too!
    You can divide the runtime overhead by two as many times as you want.

CommandLine:
    python -m ubelt.progiter __doc__:0

Example:
    >>> # xdoctest: +SKIP
    >>> import progiter
    >>> def is_prime(n):
    ...     return n >= 2 and not any(n % i == 0 for i in range(2, n))
    >>> for n in progiter.ProgIter(range(1000000), verbose=1):
    >>>     # do some work
    >>>     is_prime(n)

Example:
    >>> import ubelt as ub
    >>> for n in ub.ProgIter(range(1000)):
    >>>     # do some work
    >>>     pass
"""
from __future__ import (absolute_import, division, print_function,
                        unicode_literals)
import sys
import time
import collections


__all__ = [
    'ProgIter',
]

if sys.version_info.major > 2:  # nocover
    text_type = str
    string_types = str,
    default_timer = time.perf_counter
else:   # nocover
    # text_type = unicode
    # string_types = basestring,
    text_type = eval('unicode', {}, {})
    string_types = (eval('basestring', {}, {}),)
    default_timer = time.clock if sys.platform.startswith('win32') else time.time


CLEAR_BEFORE = '\r'
AT_END = '\n'
CLEAR_AFTER = ''


def _infer_length(iterable):
    """
    Try and infer the length using the PEP 424 length hint if available.

    adapted from click implementation
    """
    try:
        return len(iterable)
    except (AttributeError, TypeError):  # nocover
        try:
            get_hint = type(iterable).__length_hint__
        except AttributeError:
            return None
        try:
            hint = get_hint(iterable)
        except TypeError:
            return None
        if (hint is NotImplemented or
             not isinstance(hint, int) or
             hint < 0):
            return None
        return hint


class _TQDMCompat(object):
    """
    Base class for ProgIter that implements a restricted TQDM Compatibility API
    """

    @classmethod
    def write(cls, s, file=None, end='\n', nolock=False):
        """ simply writes to stdout """
        fp = file if file is not None else sys.stdout
        fp.write(s)
        fp.write(end)

    def set_description(self, desc=None, refresh=True):
        """ tqdm api compatibility. Changes the description of progress """
        self.desc = desc
        if refresh:
            self.refresh()

    def set_description_str(self, desc=None, refresh=True):
        """ tqdm api compatibility. Changes the description of progress """
        self.set_description(desc, refresh)

    def update(self, n=1):
        """ alias of `step` for tqdm compatibility """
        self.step(n)

    def close(self):
        """ alias of `end` for tqdm compatibility """
        self.end()

    def unpause(self):
        """ tqdm api compatibility. does nothing """
        pass

    def moveto(self, n):
        """ tqdm api compatibility. does nothing """
        pass

    def clear(self, nolock=False):
        """ tqdm api compatibility. does nothing """
        pass

    def refresh(self, nolock=False):
        """
        tqdm api compatibility. redisplays message
        (can cause a message to print twice)
        """
        if not self.started:
            self.begin()
        self.display_message()

    @property
    def pos(self):
        return 0

    @classmethod
    def set_lock(cls, lock):
        """ tqdm api compatibility. does nothing """
        pass

    @classmethod
    def get_lock(cls):
        """ tqdm api compatibility. does nothing """
        pass

    def set_postfix(self, ordered_dict=None, refresh=True, **kwargs):
        """ tqdm api compatibility. calls set_extra """
        # Sort in alphabetical order to be more deterministic
        postfix = collections.OrderedDict(
            [] if ordered_dict is None else ordered_dict)
        for key in sorted(kwargs.keys()):
            postfix[key] = kwargs[key]
        # Preprocess stats according to datatype
        for key in postfix.keys():
            import numbers
            # Number: limit the length of the string
            if isinstance(postfix[key], numbers.Number):
                postfix[key] = '{0:2.3g}'.format(postfix[key])
            # Else for any other type, try to get the string conversion
            elif not isinstance(postfix[key], string_types):
                postfix[key] = str(postfix[key])
            # Else if it's a string, don't need to preprocess anything
        # Stitch together to get the final postfix
        postfix = ', '.join(key + '=' + postfix[key].strip()
                                 for key in postfix.keys())
        self.set_postfix_str(postfix, refresh=refresh)

    def set_postfix_str(self, s='', refresh=True):
        """ tqdm api compatibility. calls set_extra """
        self.set_extra(str(s))
        if refresh:
            self.refresh()


class _BackwardsCompat(object):
    """
    Base class for ProgIter that maintains backwards compatibility with older
    versions of the ProgIter API.
    """

    # Backwards Compatibility API
    @property
    def length(self):
        """ alias of total """
        return self.total

    @property
    def label(self):
        """ alias of desc """
        return self.desc


[docs]class ProgIter(_TQDMCompat, _BackwardsCompat): """ Prints progress as an iterator progresses Attributes: iterable (iterable): An iterable iterable desc (str): description label to show with progress total (int): Maximum length of the process (estimated from iterable if not specified) freq (int): How many iterations to wait between messages. adjust (bool): if True freq is adjusted based on time_thresh eta_window (int): number of previous measurements to use in eta calculation clearline (bool): if true messages are printed on the same line adjust (bool): if True `freq` is adjusted based on time_thresh time_thresh (float): desired amount of time to wait between messages if adjust is True otherwise does nothing show_times (bool): shows rate, eta, and wall (defaults to True) initial (int): starting index offset (defaults to 0) stream (file): defaults to sys.stdout enabled (bool): if False nothing happens. chunksize (int): indicates that each iteration processes a batch of this size. Iteration rate is displayed in terms of single-items. verbose (int): verbosity mode 0 - no verbosity, 1 - verbosity with clearline=True and adjust=True 2 - verbosity without clearline=False and adjust=True 3 - verbosity without 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: >>> # xdoctest: +SKIP >>> 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): >>> # do some work >>> is_prime(n) 100/100... rate=... Hz, total=..., wall=... EST """ def __init__(self, iterable=None, desc=None, total=None, freq=1, initial=0, eta_window=64, clearline=True, adjust=True, time_thresh=2.0, show_times=True, enabled=True, verbose=None, stream=None, chunksize=None, **kwargs): """ Notes: See attributes for arg information **kwargs accepts most of the tqdm api """ if desc is None: desc = '' if verbose is not None: if verbose <= 0: # nocover enabled = False elif verbose == 1: # nocover enabled, clearline, adjust = 1, 1, 1 elif verbose == 2: # nocover enabled, clearline, adjust = 1, 0, 1 elif verbose >= 3: # nocover enabled, clearline, adjust = 1, 0, 0 # Potential new additions to the API self._microseconds = kwargs.pop('microseconds', False) # --- Accept the tqdm api --- if kwargs: stream = kwargs.pop('file', stream) enabled = not kwargs.pop('disable', not enabled) if kwargs.get('miniters', None) is not None: adjust = False freq = kwargs.pop('miniters', freq) kwargs.pop('position', None) # API compatability does nothing kwargs.pop('dynamic_ncols', None) # API compatability does nothing kwargs.pop('leave', True) # we always leave # Accept the old api keywords desc = kwargs.pop('label', desc) total = kwargs.pop('length', total) enabled = kwargs.pop('enabled', enabled) initial = kwargs.pop('start', initial) if kwargs: raise ValueError('ProgIter given unknown kwargs {}'.format(kwargs)) # ---------------------------- if stream is None: stream = sys.stdout self.stream = stream self.iterable = iterable self.desc = desc self.total = total self.freq = freq self.initial = initial self.enabled = enabled self.adjust = adjust self.show_times = show_times self.eta_window = eta_window self.time_thresh = 1.0 self.clearline = clearline self.chunksize = chunksize self.extra = '' self.started = False self.finished = False self._reset_internals() def __call__(self, iterable): self.iterable = iterable return iter(self) def __enter__(self): """ Example: >>> # can be used as a context manager in iter mode >>> n = 3 >>> with ProgIter(desc='manual', total=n, verbose=3) as prog: ... list(prog(range(n))) """ self.begin() return self def __exit__(self, type, value, trace): if trace is not None: return False else: self.end() def __iter__(self): if not self.enabled: return iter(self.iterable) else: return self._iterate()
[docs] def set_extra(self, 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 """ self.extra = extra
def _iterate(self): """ iterates with progress """ if not self.started: self.begin() # Wrap input sequence in a generator for self._iter_idx, item in enumerate(self.iterable, start=self.initial + 1): yield item if (self._iter_idx) % self.freq == 0: # update progress information every so often self._update_measurements() self._update_estimates() self.display_message() self.end()
[docs] def step(self, inc=1): """ Manually step progress update, either directly or by an increment. Args: idx (int): current step index (default None) if specified, takes precidence over `inc` inc (int): number of steps to increment (defaults to 1) 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() """ if not self.enabled: return self._iter_idx += inc self._update_measurements() self._update_estimates() self.display_message()
def _reset_internals(self): """ Initialize all variables used in the internal state """ # Prepare for iteration if self.total is None: self.total = _infer_length(self.iterable) self._est_seconds_left = None self._total_seconds = 0 self._between_time = 0 self._iter_idx = self.initial self._last_idx = self.initial - 1 # now time is actually not right now # now refers the the most recent measurment # last refers to the measurement before that self._now_idx = self.initial self._now_time = 0 self._between_count = -1 self._max_between_time = -1.0 self._max_between_count = -1.0 self._iters_per_second = 0.0 self._update_message_template()
[docs] def begin(self): """ 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. """ if not self.enabled: return self._reset_internals() self._tryflush() self.display_message() # Time progress was initialized self._start_time = default_timer() # Last time measures were udpated self._last_time = self._start_time self._now_idx = self._iter_idx self._now_time = self._start_time # use last few times to compute a more stable average rate if self.eta_window is not None: self._measured_times = collections.deque( [], maxlen=self.eta_window) self._measured_times.append((self._iter_idx, self._start_time)) # self._cursor_at_newline = True self._cursor_at_newline = not self.clearline self.started = True self.finished = False
[docs] def end(self): """ 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. """ if not self.enabled or self.finished: return # Write the final progress line if it was not written in the loop if self._iter_idx != self._now_idx: self._update_measurements() self._update_estimates() self._est_seconds_left = 0 self.display_message() self.ensure_newline() self._cursor_at_newline = True self.finished = True
def _adjust_frequency(self): # Adjust frequency so the next print will not happen until # approximatly `time_thresh` seconds have passed as estimated by # iter_idx. eps = 1E-9 self._max_between_time = max(self._max_between_time, self._between_time) self._max_between_time = max(self._max_between_time, eps) self._max_between_count = max(self._max_between_count, self._between_count) # If progress was uniform and all time estimates were # perfect this would be the new freq to achieve self.time_thresh new_freq = int(self.time_thresh * self._max_between_count / self._max_between_time) new_freq = max(new_freq, 1) # But things are not perfect. So, don't make drastic changes factor = 1.5 max_freq_change_up = max(256, int(self.freq * factor)) max_freq_change_down = int(self.freq // factor) if (new_freq - self.freq) > max_freq_change_up: self.freq += max_freq_change_up elif (self.freq - new_freq) > max_freq_change_down: self.freq -= max_freq_change_down else: self.freq = new_freq def _update_measurements(self): """ update current measurements and estimated of time and progress """ self._last_idx = self._now_idx self._last_time = self._now_time self._now_idx = self._iter_idx self._now_time = default_timer() self._between_time = self._now_time - self._last_time self._between_count = self._now_idx - self._last_idx self._total_seconds = self._now_time - self._start_time # Record that measures were updated def _update_estimates(self): # Estimate rate of progress if self.eta_window is None: self._iters_per_second = self._now_idx / self._total_seconds else: # Smooth out rate with a window self._measured_times.append((self._now_idx, self._now_time)) prev_idx, prev_time = self._measured_times[0] self._iters_per_second = ((self._now_idx - prev_idx) / (self._now_time - prev_time)) if self.total is not None: # Estimate time remaining if total is given iters_left = self.total - self._now_idx est_eta = iters_left / self._iters_per_second self._est_seconds_left = est_eta # Adjust frequency if printing too quickly # so progress doesnt slow down actual function if self.adjust and (self._between_time < self.time_thresh or self._between_time > self.time_thresh * 2.0): self._adjust_frequency() def _update_message_template(self): self._msg_fmtstr = self._build_message_template() def _build_message_template(self): """ Defines the template for the progress line Example: >>> self = ProgIter(show_times=True) >>> print(self._build_message_template().strip()) {desc} {iter_idx:4d}/?...{extra} rate={rate:{rate_format}} Hz, total={total}, wall={wall} ... >>> self = ProgIter(show_times=False) >>> print(self._build_message_template().strip()) {desc} {iter_idx:4d}/?...{extra} """ from math import log10, floor tzname = time.tzname[0] length_unknown = self.total is None or self.total <= 0 if length_unknown: n_chrs = 4 else: n_chrs = int(floor(log10(float(self.total))) + 1) if self.chunksize and not length_unknown: msg_body = [ ('{desc}'), (' {percent:03.2f}% of ' + str(self.chunksize) + 'x'), ('?' if length_unknown else text_type(self.total)), ('...'), ] else: msg_body = [ ('{desc}'), (' {iter_idx:' + str(n_chrs) + 'd}/'), ('?' if length_unknown else text_type(self.total)), ('...'), ] msg_body += [ ('{extra} '), ] if self.show_times: msg_body += [ ('rate={rate:{rate_format}} Hz,'), (' eta={eta},' if self.total else ''), (' total={total},'), # this is total time (' wall={wall} ' + tzname), ] if self.clearline: msg_body = [CLEAR_BEFORE] + msg_body + [CLEAR_AFTER] else: msg_body = msg_body + [AT_END] msg_fmtstr_time = ''.join(msg_body) return msg_fmtstr_time
[docs] def format_message(self): r""" builds a formatted progres 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' """ from datetime import timedelta if self._est_seconds_left is None: eta = '?' else: if self._microseconds: eta = text_type(timedelta(seconds=self._est_seconds_left)) else: eta = text_type(timedelta(seconds=int(self._est_seconds_left))) if self._microseconds: total = text_type(timedelta(seconds=self._total_seconds)) else: total = text_type(timedelta(seconds=int(self._total_seconds))) # similar to tqdm.format_meter if self.chunksize and self.total: msg = self._msg_fmtstr.format( desc=self.desc, percent=self._now_idx / self.total * 100, rate=self._iters_per_second * self.chunksize, rate_format='4.2f' if self._iters_per_second * self.chunksize > .001 else 'g', eta=eta, total=total, wall=time.strftime('%H:%M'), extra=self.extra, ) else: msg = self._msg_fmtstr.format( desc=self.desc, iter_idx=self._now_idx, rate=self._iters_per_second, rate_format='4.2f' if self._iters_per_second > .001 else 'g', eta=eta, total=total, wall=time.strftime('%H:%M'), extra=self.extra, ) return msg
[docs] def ensure_newline(self): """ 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(4), show_times=False, verbose=1) >>> for n in prog: ... print('unsafe message') 0/4... unsafe message 1/4... unsafe message unsafe message unsafe message 4/4... >>> # apparently the safe version does this too. >>> print('---') --- >>> prog = ProgIter(range(4), show_times=False, verbose=1) >>> for n in prog: ... prog.ensure_newline() ... print('safe message') 0/4... safe message 1/4... safe message safe message safe message 4/4... """ if not self._cursor_at_newline: self._write(AT_END) self._cursor_at_newline = True
[docs] def display_message(self): """ Writes current progress to the output stream """ msg = self.format_message() self._write(msg) self._tryflush() self._cursor_at_newline = not self.clearline
def _tryflush(self): """ flush to the internal stream """ try: # flush sometimes causes issues in IPython notebooks self.stream.flush() except IOError: # nocover pass def _write(self, msg): """ write to the internal stream """ self.stream.write(msg)
if __name__ == '__main__': import xdoctest as xdoc xdoc.doctest_module()