tqdm
tqdm
(read taqadum, تقدّم) means "progress" in arabic.
Instantly make your loops show a smart progress meter - just wrap any iterable with "tqdm(iterable)", and you're done!
from tqdm import tqdm
for i in tqdm(range(9)):
...
Here's what the output looks like:
76%|████████████████████ | 7641/10000 [00:34<00:10, 222.22 it/s]
trange(N)
can be also used as a convenient shortcut for
tqdm(xrange(N))
.
Overhead is low -- about 60ns per iteration (80ns with gui=True
).
By comparison, the well established
ProgressBar has
an 800ns/iter overhead.
In addition to its low overhead, tqdm
uses smart algorithms to predict
the remaining time and to skip unneccessary iteration displays, which allows
for a negligible overhead in most cases.
tqdm
works on any platform (Linux/Windows/Mac), in any console or in a
GUI, and is also friendly with IPython/Jupyter notebooks.
tqdm
does not require any library (not even curses!) to run, just a
vanilla Python interpreter will do.
Table of contents
Installation
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
Usage
tqdm
is very versatile and can be used in a number of ways.
The two main ones are given below.
Iterable-based
Wrap tqdm()
around any iterable:
for char in tqdm(["a", "b", "c", "d"]):
print 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 close()
at the end:
pbar = tqdm(total=100):
for i in range(10):
pbar.update(10)
pbar.close()
Documentation
class tqdm(object):
"""
Decorate an iterable object, returning an iterator which acts exactly
like the orignal iterable, but prints a dynamically updating
progressbar every time a value is requested.
"""
def __init__(self, iterable=None, desc=None, total=None, leave=False,
file=sys.stderr, ncols=None, mininterval=0.1,
maxinterval=10.0, miniters=None, ascii=None, disable=False,
unit='it', unit_scale=False, dynamic_ncols=False,
smoothing=0.3, nested=False):
Parameters
- iterable : iterable, optional
Iterable to decorate with a progressbar. Leave blank [default: None] to manually manage the updates.
- desc : str, optional
Prefix for the progressbar [default: None].
- total : int, optional
The number of expected iterations. If not given, 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).
- leave : bool, optional
If [default: False], removes all traces of the progressbar upon termination of iteration.
- file : io.TextIOWrapper or io.StringIO, optional
Specifies where to output the progress messages [default: sys.stderr]. Uses file.write(str) and file.flush() methods.
- ncols : int, optional
The width of the entire output message. If specified, dynamically resizes the progressbar to stay within this bound. If [default: None], 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).
- mininterval : float, optional
Minimum progress update interval, in seconds [default: 0.1].
- maxinterval : float, optional
Maximum progress update interval, in seconds [default: 10.0].
- miniters : int, optional
Minimum progress update interval, in iterations [default: None]. If specified, will set mininterval to 0.
- ascii : bool, optional
If [default: None] or false, use unicode (smooth blocks) to fill the meter. The fallback is to use ASCII characters 1-9 #.
- disable : bool
Whether to disable the entire progressbar wrapper [default: False].
- unit : str, optional
String that will be used to define the unit of each iteration [default: 'it'].
- unit_scale : bool, 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_ncols : bool, optional
If set, constantly alters ncols to the environment (allowing for window resizes) [default: False].
- smoothing : float
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].
- nested : bool, optional
Whether this iterable is nested in another one also managed by tqdm [default: False]. Allows display of multiple, nested progress bars.
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 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!
"""
Examples and Advanced Usage
See the examples folder or
import the module and run help()
.
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 onceon establishment of the network connection and once after each block readthereafter. The hook will be passed three arguments; a count of blockstransferred 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, leave=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 DataFrameGroupBy.progress_apply
:
import pandas as pd
import numpy as np
from tqdm import tqdm, tqdm_pandas
df = pd.DataFrame(np.random.randint(0, 100, (100000, 6)))
# Create and register a new `tqdm` instance with `pandas`
# (can use tqdm_gui, optional kwargs, etc.)
tqdm_pandas(tqdm())
# Now you can use `progress_apply` instead of `apply`
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()
.
Nested progress bars
tqdm
supports nested progress bars, you just need to specify the
nested=True argument for all tqdm instanciation except the outermost
bar. Here's an example:
from tqdm import trange
from time import sleep
for i in trange(10, desc='1st loop', leave=True):
for j in trange(5, desc='2nd loop', leave=True, nested=True):
for k in trange(100, desc='3nd loop', leave=True, nested=True):
sleep(0.01)
On Windows colorama will be used if available to produce a beautiful nested display.
How to make a good progress bar
A good progress bar is a useful progress bar. To be useful, tqdm
displays
statistics and uses smart algorithms to predict and automagically adapt to
a variety of use cases with no or minimal configuration.
However, there is one thing that tqdm
cannot do: choose a pertinent
progress indicator. To display a useful progress bar, it is very important that
you ensure that you supply tqdm
with the most pertinent progress indicator,
which will reflect most accurately the current state of your program.
Usually, a good way is to preprocess quickly to first evaluate the total amount
of work to do before beginning the real processing.
To illustrate the importance of a good progress indicator, let's take the following example: you want to walk through all files of a directory and process their contents to do your biddings.
Here is a basic program to do that:
import os
from tqdm import tqdm, trange
from time import sleep
def dosomething(buf):
"""Do something with the content of a file"""
sleep(0.01)
pass
def walkdir(folder):
"""Walk through each files in a directory"""
for dirpath, dirs, files in os.walk(folder):
for filename in files:
yield os.path.abspath(os.path.join(dirpath, filename))
def process_content_no_progress(inputpath, blocksize=1024):
for filepath in walkdir(inputpath):
with open(filepath, 'rb') as fh:
buf = 1
while (buf):
buf = fh.read(blocksize)
dosomething(buf)
process_content_no_progress()
does the job alright, but it does not show
any information about the current progress, nor how long it will take.
To quickly fix that using tqdm
, we can use this naive approach:
def process_content_with_progress1(inputpath, blocksize=1024):
for filepath in tqdm(walkdir(inputpath), leave=True):
with open(filepath, 'rb') as fh:
buf = 1
while (buf):
buf = fh.read(blocksize)
dosomething(buf)
process_content_with_progress1()
will load tqdm()
, but since the
iterator does not provide any length (os.walkdir()
does not have a
__len__()
method for the total files count), there is only an indication
of the current and past program state, no prediction:
4it [00:03, 2.79it/s]
The way to get predictive information is to know the total amount of work to be
done. Since os.walkdir()
cannot give us this information, we need to
precompute this by ourselves:
def process_content_with_progress2(inputpath, blocksize=1024):
# Preprocess the total files count
filecounter = 0
for dirpath, dirs, files in tqdm(os.walk(inputpath)):
for filename in files:
filecounter += 1
for filepath in tqdm(walkdir(inputpath), total=filecounter, leave=True):
with open(filepath, 'rb') as fh:
buf = 1
while (buf):
buf = fh.read(blocksize)
dosomething(buf)
process_content_with_progress2()
is better than the naive approach because
now we have predictive information:
50%|██████████████████████ | 2/4 [00:00<00:00, 4.06it/s]
However, the progress is not smooth: it increments in steps, 1 step being 1 file processed. The problem is that we do not just walk through files tree, but we process the files contents. Thus, if we stumble on one big fat file, it will take a huge deal more time to process than other smaller files, but the progress bar cannot know that, because we only supplied the files count, so it considers that every element is of equal processing weight.
To fix this, we should use another indicator than the files count: the total sum of all files sizes. This would be more pertinent since the data we process is the files' content, so there is a direct relation between size and content.
Below we implement this approach using a manually updated tqdm
bar, where
tqdm
will work on size, while the for
loop works on files paths:
def process_content_with_progress3(inputpath, blocksize=1024):
# Preprocess the total files sizes
sizecounter = 0
for dirpath, dirs, files in tqdm(os.walk(inputpath)):
for filename in files:
fullpath = os.path.abspath(os.path.join(dirpath, filename))
sizecounter += os.stat(fullpath).st_size
# Load tqdm with size counter instead of files counter
with tqdm(total=sizecounter, leave=True, unit='B', unit_scale=True) as pbar:
for dirpath, dirs, files in os.walk(inputpath):
for filename in files:
fullpath = os.path.abspath(os.path.join(dirpath, filename))
with open(fullpath, 'rb') as fh:
buf = 1
while (buf):
buf = fh.read(blocksize)
dosomething(buf)
if buf: pbar.update(len(buf))
And here is the result: a much smoother progress bar with meaningful predicted time and statistics:
47%|██████████████████▍ | 152K/321K [00:03<00:03, 46.2KB/s]
Contributions
To run the testing suite please make sure tox (https://testrun.org/tox/latest/)
is installed, then type tox
from the command line.
Where tox
is unavailable, a Makefile-like setup is
provided with the following command:
$ python setup.py make alltests
To see all options, run:
$ python setup.py make
See the CONTRIBUTE file for more information.
License
Authors
- Casper da Costa-Luis (casperdcl)
- Stephen Larroque (lrq3000)
- Hadrien Mary (hadim)
- Noam Yorav-Raphael (noamraph)*
- Ivan Ivanov (obiwanus)
- Mikhail Korobov (kmike)
* Original author