Python Progress Bar

How do I use a progress bar when my script is doing some task that is likely to take time?

For example, a function which takes some time to complete and returns True when done. How can I display a progress bar during the time the function is being executed?

Note that I need this to be in real time, so I can't figure out what to do about it. Do I need a thread for this? I have no idea.

Right now I am not printing anything while the function is being executed, however a progress bar would be nice. Also I am more interested in how this can be done from a code point of view.

Solution 1:

With tqdm (conda install tqdm or pip install tqdm) you can add a progress meter to your loops in a second:

from time import sleep
from tqdm import tqdm
for i in tqdm(range(10)):
    sleep(3)

 60%|██████    | 6/10 [00:18<00:12,  0.33 it/s]

Also, there is a notebook version:

from tqdm.notebook import tqdm
for i in tqdm(range(100)):
    sleep(3)

You can use tqdm.auto instead of tqdm.notebook to work in both a terminal and notebooks.

tqdm.contrib contains some helper functions to do things like enumerate, map, and zip. There are concurrent maps in tqdm.contrib.concurrent.

You can even get progress sent to your phone after disconnecting from a jupyter notebook using tqdm.contrib.telegram or tqdm.contrib.discord.

Solution 2:

There are specific libraries (like this one here) but maybe something very simple would do:

import time
import sys

toolbar_width = 40

# setup toolbar
sys.stdout.write("[%s]" % (" " * toolbar_width))
sys.stdout.flush()
sys.stdout.write("\b" * (toolbar_width+1)) # return to start of line, after '['

for i in xrange(toolbar_width):
    time.sleep(0.1) # do real work here
    # update the bar
    sys.stdout.write("-")
    sys.stdout.flush()

sys.stdout.write("]\n") # this ends the progress bar

Note: progressbar2 is a fork of progressbar which hasn't been maintained in years.

Solution 3:

Use alive-progress, the coolest progress bar ever!

To use any progress bar framework in a useful manner, i.e. to get a percentage of completion and an estimated time of arrival (ETA), you need to be able to tell how many steps your processing will have.

Then you can just insert an yield to mark an item has been processed, and you're good to go!

def compute():
    for i in range(1000):
        ... # process items as usual.
        yield  # insert this :)

Then just use it like:

from alive_progress import alive_bar

with alive_bar(1000) as bar:
    for i in compute():
        bar()

To get an awesome and alive progress bar!

|█████████████▎                      | ▅▃▁ 321/1000 [32%] in 8s (40.1/s, eta: 16s)

Disclaimer: I'm the author of alive-progress, but it should solve your problem nicely! Read the documentation at https://github.com/rsalmei/alive-progress to know more. Now it works also on Jupyter Notebooks! Here are some more examples of what it can do: