"""
A Progress Iterator
ProgIter lets you measure and print the progress of an iterative process. This
can be done either via an iterable interface or using the manual API. Using the
iterable interface is most common.
ProgIter was originally developed independently of tqdm, but the newer versions
of this library have been designed to be compatible with tqdm-API.
:class:`ProgIter` is now a (mostly) drop-in alternative to :func:`tqdm.tqdm`. The
:mod:`tqdm` library may be more appropriate in some cases. *The main advantage of
:class:`ProgIter` is that it does not use any python threading*, and therefore can
be safer with code that makes heavy use of multiprocessing.
`The reason <https://pybay.com/site_media/slides/raymond2017-keynote/combo.html>`_
for this is that threading before forking may cause locks to be duplicated
across processes, which may lead to deadlocks.
ProgIter is simpler than tqdm, which may be desirable for some applications.
However, this also means ProgIter is not as extensible as tqdm.
If you want a pretty bar or need something fancy, use tqdm;
if you want useful information about your iteration by default, use progiter.
The basic usage of ProgIter is simple and intuitive. Just wrap a python
iterable. The following example wraps a ``range`` iterable and prints reported
progress to stdout as the iterable is consumed.
Example:
>>> for n in ProgIter(range(1000)):
>>> # do some work
>>> pass
Note that by default ProgIter reports information about iteration-rate,
fraction-complete, estimated time remaining, time taken so far, and the current
wall time.
Example:
>>> # xdoctest: +IGNORE_WANT
>>> def is_prime(n):
... return n >= 2 and not any(n % i == 0 for i in range(2, n))
>>> for n in ProgIter(range(1000), verbose=1):
>>> # do some work
>>> is_prime(n)
1000/1000... rate=114326.51 Hz, eta=0:00:00, total=0:00:00
For more complex applications is may sometimes be desirable to
manually use the ProgIter API. This is done as follows:
Example:
>>> # xdoctest: +IGNORE_WANT
>>> n = 3
>>> prog = ProgIter(desc='manual', total=n, verbose=3)
>>> prog.begin() # Manually begin progress iteration
>>> for _ in range(n):
... prog.step(inc=1) # specify the number of steps to increment
>>> prog.end() # Manually end progress iteration
manual 0/3... rate=0 Hz, eta=?, total=0:00:00
manual 1/3... rate=14454.63 Hz, eta=0:00:00, total=0:00:00
manual 2/3... rate=17485.42 Hz, eta=0:00:00, total=0:00:00
manual 3/3... rate=21689.78 Hz, eta=0:00:00, total=0:00:00
When working with ProgIter in either iterable or manual mode you can use the
``prog.ensure_newline`` method to guarantee that the next call you make to
stdout will start on a new line. You can also use the ``prog.set_extra`` method
to update a dynamci "extra" message that is shown in the formatted output. The
following example demonstrates this.
Example:
>>> # xdoctest: +IGNORE_WANT
>>> def is_prime(n):
... return n >= 2 and not any(n % i == 0 for i in range(2, n))
>>> _iter = range(1000)
>>> prog = ProgIter(_iter, desc='check primes', verbose=2, show_wall=True)
>>> for n in prog:
>>> if n == 97:
>>> print('!!! Special print at n=97 !!!')
>>> if is_prime(n):
>>> prog.set_extra('Biggest prime so far: {}'.format(n))
>>> prog.ensure_newline()
check primes 0/1000... rate=0 Hz, eta=?, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 1/1000... rate=95547.49 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 4/1000...Biggest prime so far: 3 rate=41062.28 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 16/1000...Biggest prime so far: 13 rate=85340.61 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 64/1000...Biggest prime so far: 61 rate=164739.98 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
!!! Special print at n=97 !!!
check primes 256/1000...Biggest prime so far: 251 rate=206287.91 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 512/1000...Biggest prime so far: 509 rate=165271.92 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 768/1000...Biggest prime so far: 761 rate=136480.12 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
check primes 1000/1000...Biggest prime so far: 997 rate=115214.95 Hz, eta=0:00:00, total=0:00:00, wall=2020-10-23 17:27 EST
TODO:
- [ ] Specify callback that occurs whenever progress is written?
"""
import sys
import time
import collections
__all__ = [
'ProgIter',
]
default_timer = time.perf_counter
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], str):
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
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.
Attributes:
iterable (List | Iterable):
A list or iterable to loop over
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):
How many iterations to wait between messages.
Defaults to 1.
adjust (bool):
if True freq is adjusted based on time_thresh
Defaults to True.
eta_window (int):
number of previous measurements to use in eta calculation, default=64
clearline (bool):
if True messages are printed on the same line otherwise each new
progress message is printed on new line.
default=True
adjust (bool):
if True `freq` is adjusted based on time_thresh. This may be
overwritten depending on the setting of verbose.
default=True
time_thresh (float):
desired amount of time to wait between messages if adjust is True
otherwise does nothing, default=2.0
show_times (bool):
shows rate and eta, default=True
show_wall (bool):
show wall time, default=False
initial (int):
starting index offset, default=0
stream (typing.IO):
stream where progress information is written to, default=sys.stdout
enabled (bool): if False nothing happens. default=True
chunksize (int | None):
indicates that each iteration processes a batch of this size.
Iteration rate is displayed in terms of single-items.
rel_adjust_limit (float):
Maximum factor update frequency can be adjusted by in a single
step. default=4.0
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:
>>> # doctest: +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, show_wall=True):
>>> # do some work
>>> is_prime(n)
100/100... rate=... Hz, total=..., wall=...
"""
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, show_wall=False,
enabled=True, verbose=None, stream=None, chunksize=None,
rel_adjust_limit=4.0, **kwargs):
"""
Note:
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 compatibility does nothing
kwargs.pop('dynamic_ncols', None) # API compatibility 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)
time_thresh = kwargs.pop('mininterval', time_thresh)
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.show_wall = show_wall
self.eta_window = eta_window
self.time_thresh = time_thresh
self.clearline = clearline
self.chunksize = chunksize
self.rel_adjust_limit = rel_adjust_limit
self.extra = ''
self.started = False
self.finished = False
# indicates if the cursor is currently at the start of a line (True) or
# if characters have been written with no newline yet.
self._cursor_at_newline = True
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()
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
# Call the body of step to reduce overyead
# self.step(0) # inc is 0 because we already updated
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, force=False):
"""
Manually step progress update, either directly or by an increment.
Args:
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()
"""
if not self.enabled:
return
self._iter_idx += inc
_between_idx = (self._iter_idx - self._now_idx)
if force or _between_idx >= self.freq:
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 measurement
# 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 start(self): # nocover
"""
Alias of :func:`ubelt.progiter.ProgIter.begin`
"""
return self.begin()
[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.
Returns:
ProgIter:
a chainable self-reference
"""
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 updated
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
return self
[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
# approximately `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)
# But things are not perfect. So, don't make drastic changes
rel_limit = self.rel_adjust_limit
max_freq = int(self.freq * rel_limit)
min_freq = int(self.freq // rel_limit)
self.freq = max(min(new_freq, max_freq), min_freq, 1)
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 does not 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} ...
>>> self = ProgIter(show_times=False)
>>> print(self._build_message_template().strip())
{desc} {iter_idx:4d}/?...{extra}
>>> self = ProgIter(total=0, show_times=True)
>>> print(self._build_message_template().strip())
{desc} {iter_idx:1d}/0...{extra} rate={rate:{rate_format}} Hz, total={total} ...
"""
from math import log10, floor
length_unknown = self.total is None or self.total < 0
if length_unknown:
n_chrs = 4
else:
if self.total == 0:
n_chrs = 1
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 str(self.total)),
('...'),
]
else:
msg_body = [
('{desc}'),
(' {iter_idx:' + str(n_chrs) + 'd}/'),
('?' if length_unknown else str(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.show_wall:
msg_body += [
(', wall={wall}'),
]
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 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(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...
"""
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)