tqdm 4.11.2

Latest PyPI stable release

pip install tqdm

Latest development release on github

Pull and install in the current directory:

pip install -e git+https://github.com/tqdm/tqdm.git@master#egg=tqdm

Latest Conda release

conda install -c conda-forge tqdm

Iterable-based

Wrap tqdm() around any iterable:

text = ""
for char in tqdm(["a", "b", "c", "d"]):
    text = text + char

trange(i) is a special optimised instance of tqdm(range(i)):

for i in trange(100):
    pass

Instantiation outside of the loop allows for manual control over tqdm():

pbar = tqdm(["a", "b", "c", "d"])
for char in pbar:
    pbar.set_description("Processing %s" % char)

Manual

Manual control on tqdm() updates by using a with statement:

with tqdm(total=100) as pbar:
    for i in range(10):
        pbar.update(10)

If the optional variable total (or an iterable with len()) is provided, predictive stats are displayed.

with is also optional (you can just assign tqdm() to a variable, but in this case don’t forget to del or close() at the end:

pbar = tqdm(total=100)
for i in range(10):
    pbar.update(10)
pbar.close()

Module

Perhaps the most wonderful use of tqdm is in a script or on the command line. Simply inserting tqdm (or python -m tqdm) between pipes will pass through all stdin to stdout while printing progress to stderr.

The example below demonstrated counting the number of lines in all python files in the current directory, with timing information included.

$ time find . -name '*.py' -exec cat \{} \; | wc -l
857365

real    0m3.458s
user    0m0.274s
sys     0m3.325s

$ time find . -name '*.py' -exec cat \{} \; | tqdm | wc -l
857366it [00:03, 246471.31it/s]
857365

real    0m3.585s
user    0m0.862s
sys     0m3.358s

Note that the usual arguments for tqdm can also be specified.

$ find . -name '*.py' -exec cat \{} \; |
    tqdm --unit loc --unit_scale --total 857366 >> /dev/null
100%|███████████████████████████████████| 857K/857K [00:04<00:00, 246Kloc/s]

Backing up a large directory?

$ 7z a -bd -r backup.7z docs/ | grep Compressing |
    tqdm --total $(find docs/ -type f | wc -l) --unit files >> backup.log
100%|███████████████████████████████▉| 8014/8014 [01:37<00:00, 82.29files/s]

Parameters

• iterableiterable, optional

  Iterable to decorate with a progressbar. Leave blank to manually manage the updates.

• descstr, optional

  Prefix for the progressbar.

• totalint, optional

  The number of expected iterations. If (default: None), len(iterable) is used if possible. As a last resort, only basic progress statistics are displayed (no ETA, no progressbar). If gui is True and this parameter needs subsequent updating, specify an initial arbitrary large positive integer, e.g. int(9e9).

• leavebool, optional

  If [default: True], keeps all traces of the progressbar upon termination of iteration.

• fileio.TextIOWrapper or io.StringIO, optional

  Specifies where to output the progress messages [default: sys.stderr]. Uses file.write(str) and file.flush() methods.

• ncolsint, optional

  The width of the entire output message. If specified, dynamically resizes the progressbar to stay within this bound. If unspecified, attempts to use environment width. The fallback is a meter width of 10 and no limit for the counter and statistics. If 0, will not print any meter (only stats).

• minintervalfloat, optional

  Minimum progress display update interval, in seconds [default: 0.1].

• maxintervalfloat, optional

  Maximum progress display update interval, in seconds [default: 10]. Automatically adjusts miniters to correspond to mininterval after long display update lag. Only works if dynamic_miniters or monitor thread is enabled.

• minitersint, optional

  Minimum progress display update interval, in iterations. If 0 and dynamic_miniters, will automatically adjust to equal mininterval (more CPU efficient, good for tight loops). If > 0, will skip display of specified number of iterations. Tweak this and mininterval to get very efficient loops. If your progress is erratic with both fast and slow iterations (network, skipping items, etc) you should set miniters=1.

• asciibool, optional

  If unspecified or False, use unicode (smooth blocks) to fill the meter. The fallback is to use ASCII characters 1-9 #.

• disablebool, optional

  Whether to disable the entire progressbar wrapper [default: False].

• unitstr, optional

  String that will be used to define the unit of each iteration [default: it].

• unit_scalebool, optional

  If set, the number of iterations will be reduced/scaled automatically and a metric prefix following the International System of Units standard will be added (kilo, mega, etc.) [default: False].

• dynamic_ncolsbool, optional

  If set, constantly alters ncols to the environment (allowing for window resizes) [default: False].

• smoothingfloat, optional

  Exponential moving average smoothing factor for speed estimates (ignored in GUI mode). Ranges from 0 (average speed) to 1 (current/instantaneous speed) [default: 0.3].

• bar_formatstr, optional

  Specify a custom bar string formatting. May impact performance. If unspecified, will use ‘{l_bar}{bar}{r_bar}’, where l_bar is ‘{desc}{percentage:3.0f}%|’ and r_bar is ‘| {n_fmt}/{total_fmt} [{elapsed}<{remaining}, {rate_fmt}]’ Possible vars: bar, n, n_fmt, total, total_fmt, percentage, rate, rate_fmt, elapsed, remaining, l_bar, r_bar, desc.

• initialint, optional

  The initial counter value. Useful when restarting a progress bar [default: 0].

• positionint, optional

  Specify the line offset to print this bar (starting from 0) Automatic if unspecified. Useful to manage multiple bars at once (eg, from threads).

• postfixdict, optional

  Specify additional stats to display at the end of the bar.

Extra CLI Options

• delimchr, optional

  Delimiting character [default: ‘n’]. Use ‘0’ for null. N.B.: on Windows systems, Python converts ‘n’ to ‘rn’.

• buf_sizeint, optional

  String buffer size in bytes [default: 256] used when delim is specified.

• bytesbool, optional

  If true, will count bytes and ignore delim.

Returns

• out : decorated iterator.

  def update(self, n=1):
      """
      Manually update the progress bar, useful for streams
      such as reading files.
      E.g.:
      >>> t = tqdm(total=filesize) # Initialise
      >>> for current_buffer in stream:
      ...    ...
      ...    t.update(len(current_buffer))
      >>> t.close()
      The last line is highly recommended, but possibly not necessary if
      ``t.update()`` will be called in such a way that ``filesize`` will be
      exactly reached and printed.

      Parameters
      ----------
      n  : int
          Increment to add to the internal counter of iterations
          [default: 1].
      """

  def close(self):
      """
      Cleanup and (if leave=False) close the progressbar.
      """

  def clear(self):
      """
      Clear current bar display
      """

  def refresh(self):
      """
      Force refresh the display of this bar
      """

  def write(cls, s, file=sys.stdout, end="\n"):
      """
      Print a message via tqdm (without overlap with bars)
      """

  def set_description(self, desc=None):
      """
      Set/modify description of the progress bar.
      """

  def set_postfix(self, **kwargs):
      """
      Set/modify postfix (additional stats)
      with automatic formatting based on datatype.
      """

def trange(*args, **kwargs):
    """
    A shortcut for tqdm(xrange(*args), **kwargs).
    On Python3+ range is used instead of xrange.
    """

class tqdm_gui(tqdm):
    """
    Experimental GUI version of tqdm!
    """

def tgrange(*args, **kwargs):
    """
    Experimental GUI version of trange!
    """

class tqdm_notebook(tqdm):
    """
    Experimental IPython/Jupyter Notebook widget using tqdm!
    """

def tnrange(*args, **kwargs):
    """
    Experimental IPython/Jupyter Notebook widget using tqdm!
    """

Description and additional stats

Custom information can be displayed and updated dynamically on tqdm bars with the desc and postfix arguments:

from tqdm import trange
from random import random, randint
from time import sleep

t = trange(100)
for i in t:
    # Description will be displayed on the left
    t.set_description('GEN %i' % i)
    # Postfix will be displayed on the right, and will format automatically
    # based on argument's datatype
    t.set_postfix(loss=random(), gen=randint(1,999), str='h', lst=[1, 2])
    sleep(0.1)

Nested progress bars

tqdm supports nested progress bars. Here’s an example:

from tqdm import trange
from time import sleep

for i in trange(10, desc='1st loop'):
    for j in trange(5, desc='2nd loop', leave=False):
        for k in trange(100, desc='3nd loop'):
            sleep(0.01)

On Windows colorama will be used if available to produce a beautiful nested display.

For manual control over positioning (e.g. for multi-threaded use), you may specify position=n where n=0 for the outermost bar, n=1 for the next, and so on.

Hooks and callbacks

tqdm can easily support callbacks/hooks and manual updates. Here’s an example with urllib:

urllib.urlretrieve documentation

[…]

If present, the hook function will be called once

on establishment of the network connection and once after each block read

thereafter. The hook will be passed three arguments; a count of blocks

transferred so far, a block size in bytes, and the total size of the file.

[…]

import urllib
from tqdm import tqdm

def my_hook(t):
  """
  Wraps tqdm instance. Don't forget to close() or __exit__()
  the tqdm instance once you're done with it (easiest using `with` syntax).

  Example
  -------

  >>> with tqdm(...) as t:
  ...     reporthook = my_hook(t)
  ...     urllib.urlretrieve(..., reporthook=reporthook)

  """
  last_b = [0]

  def inner(b=1, bsize=1, tsize=None):
    """
    b  : int, optional
        Number of blocks just transferred [default: 1].
    bsize  : int, optional
        Size of each block (in tqdm units) [default: 1].
    tsize  : int, optional
        Total size (in tqdm units). If [default: None] remains unchanged.
    """
    if tsize is not None:
        t.total = tsize
    t.update((b - last_b[0]) * bsize)
    last_b[0] = b
  return inner

eg_link = 'http://www.doc.ic.ac.uk/~cod11/matryoshka.zip'
with tqdm(unit='B', unit_scale=True, miniters=1,
          desc=eg_link.split('/')[-1]) as t:  # all optional kwargs
    urllib.urlretrieve(eg_link, filename='/dev/null',
                       reporthook=my_hook(t), data=None)

It is recommend to use miniters=1 whenever there is potentially large differences in iteration speed (e.g. downloading a file over a patchy connection).

Pandas Integration

Due to popular demand we’ve added support for pandas – here’s an example for DataFrame.progress_apply and DataFrameGroupBy.progress_apply:

import pandas as pd
import numpy as np
from tqdm import tqdm

df = pd.DataFrame(np.random.randint(0, 100, (100000, 6)))

# Register `pandas.progress_apply` and `pandas.Series.map_apply` with `tqdm`
# (can use `tqdm_gui`, `tqdm_notebook`, optional kwargs, etc.)
tqdm.pandas(desc="my bar!")

# Now you can use `progress_apply` instead of `apply`
# and `progress_map` instead of `map`
df.progress_apply(lambda x: x**2)
# can also groupby:
# df.groupby(0).progress_apply(lambda x: x**2)

In case you’re interested in how this works (and how to modify it for your own callbacks), see the examples folder or import the module and run help().

IPython/Jupyter Integration

IPython/Jupyter is supported via the tqdm_notebook submodule:

from tqdm import tnrange, tqdm_notebook
from time import sleep

for i in tnrange(10, desc='1st loop'):
    for j in tqdm_notebook(xrange(100), desc='2nd loop'):
        sleep(0.01)

In addition to tqdm features, the submodule provides a native Jupyter widget (compatible with IPython v1-v4 and Jupyter), fully working nested bars and color hints (blue: normal, green: completed, red: error/interrupt, light blue: no ETA); as demonstrated below.

Writing messages

Since tqdm uses a simple printing mechanism to display progress bars, you should not write any message in the terminal using print().

To write messages in the terminal without any collision with tqdm bar display, a .write() method is provided:

from tqdm import tqdm, trange
from time import sleep

bar = trange(10)
for i in bar:
    # Print using tqdm class method .write()
    sleep(0.1)
    if not (i % 3):
        tqdm.write("Done task %i" % i)
    # Can also use bar.write()

By default, this will print to standard output sys.stdout. but you can specify any file-like object using the file argument. For example, this can be used to redirect the messages writing to a log file or class.

Redirecting writing

If using a library that can print messages to the console, editing the library by replacing print() with tqdm.write() may not be desirable. In that case, redirecting sys.stdout to tqdm.write() is an option.

To redirect sys.stdout, create a file-like class that will write any input string to tqdm.write(), and supply the arguments file=sys.stdout, dynamic_ncols=True.

A reusable canonical example is given below:

from time import sleep

import contextlib
import sys

from tqdm import tqdm

class DummyTqdmFile(object):
    """Dummy file-like that will write to tqdm"""
    file = None
    def __init__(self, file):
        self.file = file

    def write(self, x):
        # Avoid print() second call (useless \n)
        if len(x.rstrip()) > 0:
            tqdm.write(x, file=self.file)

@contextlib.contextmanager
def stdout_redirect_to_tqdm():
    save_stdout = sys.stdout
    try:
        sys.stdout = DummyTqdmFile(sys.stdout)
        yield save_stdout
    # Relay exceptions
    except Exception as exc:
        raise exc
    # Always restore sys.stdout if necessary
    finally:
        sys.stdout = save_stdout

def blabla():
    print("Foo blabla")

# Redirect stdout to tqdm.write() (don't forget the `as save_stdout`)
with stdout_redirect_to_tqdm() as save_stdout:
    # tqdm call need to specify sys.stdout, not sys.stderr (default)
    # and dynamic_ncols=True to autodetect console width
    for _ in tqdm(range(3), file=save_stdout, dynamic_ncols=True):
        blabla()
        sleep(.5)

# After the `with`, printing is restored
print('Done!')

Monitoring thread, intervals and miniters

tqdm implements a few tricks to to increase efficiency and reduce overhead.

1. Avoid unnecessary frequent bar refreshing: mininterval defines how long to wait between each refresh. tqdm always gets updated in the background, but it will diplay only every mininterval.

2. Reduce number of calls to check system clock/time.

3. mininterval is more intuitive to configure than miniters. A clever adjustment system dynamic_miniters will automatically adjust miniters to the amount of iterations that fit into time mininterval. Essentially, tqdm will check if it’s time to print without actually checking time. This behavior can be still be bypassed by manually setting miniters.

However, consider a case with a combination of fast and slow iterations. After a few fast iterations, dynamic_miniters will set miniters to a large number. When interation rate subsequently slows, miniters will remain large and thus reduce display update frequency. To address this:

4. maxinterval defines the maximum time between display refreshes. A concurrent monitoring thread checks for overdue updates and forces one where necessary.

The monitoring thread should not have a noticeable overhead, and guarantees updates at least every 10 seconds by default. This value can be directly changed by setting the monitor_interval of any tqdm instance (i.e. t = tqdm.tqdm(...); t.monitor_interval = 2). The monitor thread may be disabled application-wide by setting tqdm.tqdm.monitor_interval = 0 before instantiatiation of any tqdm bar.