[python] Python to print out status bar and percentage

To implement a status bar like below:

[==========                ]  45%
[================          ]  60%
[==========================] 100%

I want to this to be printed out to stdout, and keep refreshing it, not print to another line. How to do this?

This question is related to python

The answer is


I found useful library tqdm (https://github.com/tqdm/tqdm/, previously: https://github.com/noamraph/tqdm). It automatically estimates time of completion and can be used as iterator.

Usage:

import tqdm
import time

for i in tqdm.tqdm(range(1000)):
    time.sleep(0.01)
    # or other long operations

Results in:

|####------| 450/1000  45% [elapsed: 00:04 left: 00:05, 99.15 iters/sec]

tqdm can wrap any iterable.


As described in Mark Rushakoff's solution, you can output the carriage return character, sys.stdout.write('\r'), to reset the cursor to the beginning of the line. To generalize that solution, while also implementing Python 3's f-Strings, you could use

from time import sleep
import sys

n_bar = 50
iterable = range(33)  # for demo purposes
n_iter = len(iterable)
for i, item in enumerate(iterable):
    j = (i + 1) / n_iter

    sys.stdout.write('\r')
    sys.stdout.write(f"[{'=' * int(n_bar * j):{n_bar}s}] {int(100 * j)}%")
    sys.stdout.flush()

    sleep(0.05)  
    # do something with <item> here

Per Steven C. Howell's comment on Mark Rushakoff's answer

j = (i + 1) / n
stdout.write('\r')
stdout.write('[%-20s] %d%%' % ('='*int(20*j), 100*j))
stdout.flush()

where i is the current item and n is the total number of items


Here is something I have made using the solution by @Mark-Rushakoff. To adaptively adjust to the terminal width.

from time import sleep
import os
import sys
from math import ceil

l = list(map(int,os.popen('stty size','r').read().split()))
col = l[1]
col = col - 6

for i in range(col):
    sys.stdout.write('\r')
    getStr = "[%s " % ('='*i)
    sys.stdout.write(getStr.ljust(col)+"]"+"%d%%" % (ceil((100/col)*i)))
    sys.stdout.flush()
    sleep(0.25)
print("")

Further improving, using a function as :

import sys

def printProgressBar(i,max,postText):
    n_bar =10 #size of progress bar
    j= i/max
    sys.stdout.write('\r')
    sys.stdout.write(f"[{'=' * int(n_bar * j):{n_bar}s}] {int(100 * j)}%  {postText}")
    sys.stdout.flush()

calling example:

total=33
for i in range(total):
    printProgressBar(i,total,"blah")
    sleep(0.05)  

output:

[================================================  ] 96%  blah  

For Python 3.6 the following works for me to update the output inline:

for current_epoch in range(10):
    for current_step) in range(100):
        print("Train epoch %s: Step %s" % (current_epoch, current_step), end="\r")
print()

Easiest is still

import sys
total_records = 1000
for i in range (total_records):
    sys.stdout.write('\rUpdated record: ' + str(i) + ' of ' + str(total_records))
    sys.stdout.flush()

Key is to convert the integer type to string.


I came upon this thread today and after having tried out this solution from Mark Rushakoff

from time import sleep
import sys

for i in range(21):
sys.stdout.write('\r')
# the exact output you're looking for:
sys.stdout.write("[%-20s] %d%%" % ('='*i, 5*i))
sys.stdout.flush()
sleep(0.25)

I can say that this works fine on W7-64 with python 3.4.3 64-bit but only in the native console. However when using the built-in console of spyder 3.0.0dev, the line breaks are still/again present. As this took me some time to figure out, I'd like to report this observation here.


def printProgressBar(value,label):
    n_bar = 40 #size of progress bar
    max = 100
    j= value/max
    sys.stdout.write('\r')
    bar = '¦' * int(n_bar * j)
    bar = bar + '-' * int(n_bar * (1-j))

    sys.stdout.write(f"{label.ljust(10)} | [{bar:{n_bar}s}] {int(100 * j)}% ")
    sys.stdout.flush()

call:

printProgressBar(30,"IP")

IP | [¦¦¦¦¦¦¦¦¦¦¦¦----------------------------] 30%


You can use \r (carriage return). Demo:

import sys
total = 10000000
point = total / 100
increment = total / 20
for i in xrange(total):
    if(i % (5 * point) == 0):
        sys.stdout.write("\r[" + "=" * (i / increment) +  " " * ((total - i)/ increment) + "]" +  str(i / point) + "%")
        sys.stdout.flush()

import progressbar
import time

# Function to create  
def animated_marker():
    widgets = ['Loading: ', progressbar.Bar('=', '[', ']', '-'), progressbar.Percentage()]
    bar = progressbar.ProgressBar(max_value=200,widgets=widgets).start() 
      
    for i in range(200): 
        time.sleep(0.1)
        bar.update(i+1)
    bar.finish()

# Driver's code 
animated_marker()

Using @Mark-Rushakoff answer, I worked out a simpler approach, no need to call the sys library. It works with Python 3. Tested in Windows:

from time import sleep
for i in range(21):
    # the exact output you're looking for:
    print ("\r[%-20s] %d%%" % ('='*i, 5*i), end='')
    sleep(0.25)

Here you can use following code as a function:

def drawProgressBar(percent, barLen = 20):
    sys.stdout.write("\r")
    progress = ""
    for i in range(barLen):
        if i < int(barLen * percent):
            progress += "="
        else:
            progress += " "
    sys.stdout.write("[ %s ] %.2f%%" % (progress, percent * 100))
    sys.stdout.flush()

With use of .format:

def drawProgressBar(percent, barLen = 20):
    # percent float from 0 to 1. 
    sys.stdout.write("\r")
    sys.stdout.write("[{:<{}}] {:.0f}%".format("=" * int(barLen * percent), barLen, percent * 100))
    sys.stdout.flush()

The '\r' character (carriage return) resets the cursor to the beginning of the line and allows you to write over what was previously on the line.

from time import sleep
import sys

for i in range(21):
    sys.stdout.write('\r')
    # the exact output you're looking for:
    sys.stdout.write("[%-20s] %d%%" % ('='*i, 5*i))
    sys.stdout.flush()
    sleep(0.25)

I'm not 100% sure if this is completely portable across all systems, but it works on Linux and OSX at the least.


Try PyProg. PyProg is an open-source library for Python to create super customizable progress indicators & bars.

It is currently at version 1.0.2; it is hosted on Github and available on PyPI (Links down below). It is compatible with Python 3 & 2 and it can also be used with Qt Console.

It is really easy to use. The following code:

import pyprog
from time import sleep

# Create Object
prog = pyprog.ProgressBar(" ", " ", total=34, bar_length=26, complete_symbol="=", not_complete_symbol=" ", wrap_bar_prefix=" [", wrap_bar_suffix="] ", progress_explain="", progress_loc=pyprog.ProgressBar.PROGRESS_LOC_END)
# Update Progress Bar
prog.update()

for i in range(34):
    # Do something
    sleep(0.1)
    # Set current status
    prog.set_stat(i + 1)
    # Update Progress Bar again
    prog.update()

# Make the Progress Bar final
prog.end()

will produce exactly what you want (even the bar length!):

[===========               ] 45%
[===============           ] 60%
[==========================] 100%

For more options to customize the progress bar, go to the Github page of this website.

I actually made PyProg because I needed a simple but super customizable progress bar library. You can easily install it with: pip install pyprog.

PyProg Github: https://github.com/Bill13579/pyprog
PyPI: https://pypi.python.org/pypi/pyprog/


Building on some of the answers here and elsewhere, I've written this simple function which displays a progress bar and elapsed/estimated remaining time. Should work on most unix-based machines.

import time
import sys

percent = 50.0
start = time.time()
draw_progress_bar(percent, start)


def draw_progress_bar(percent, start, barLen=20):
sys.stdout.write("\r")
progress = ""
for i in range(barLen):
    if i < int(barLen * percent):
        progress += "="
    else:
        progress += " "

elapsedTime = time.time() - start;
estimatedRemaining = int(elapsedTime * (1.0/percent) - elapsedTime)

if (percent == 1.0):
    sys.stdout.write("[ %s ] %.1f%% Elapsed: %im %02is ETA: Done!\n" % 
        (progress, percent * 100, int(elapsedTime)/60, int(elapsedTime)%60))
    sys.stdout.flush()
    return
else:
    sys.stdout.write("[ %s ] %.1f%% Elapsed: %im %02is ETA: %im%02is " % 
        (progress, percent * 100, int(elapsedTime)/60, int(elapsedTime)%60,
         estimatedRemaining/60, estimatedRemaining%60))
    sys.stdout.flush()
    return

based on the above answers and other similar questions about CLI progress bar, I think I got a general common answer to all of them. Check it at https://stackoverflow.com/a/15860757/2254146

Here is a copy of the function, but modified to fit your style:

import time, sys

# update_progress() : Displays or updates a console progress bar
## Accepts a float between 0 and 1. Any int will be converted to a float.
## A value under 0 represents a 'halt'.
## A value at 1 or bigger represents 100%
def update_progress(progress):
    barLength = 20 # Modify this to change the length of the progress bar
    status = ""
    if isinstance(progress, int):
        progress = float(progress)
    if not isinstance(progress, float):
        progress = 0
        status = "error: progress var must be float\r\n"
    if progress < 0:
        progress = 0
        status = "Halt...\r\n"
    if progress >= 1:
        progress = 1
        status = "Done...\r\n"
    block = int(round(barLength*progress))
    text = "\rPercent: [{0}] {1}% {2}".format( "="*block + " "*(barLength-block), progress*100, status)
    sys.stdout.write(text)
    sys.stdout.flush()

Looks like

Percent: [====================] 99.0%


This is quite a simple approach can be used with any loop.

#!/usr/bin/python
for i in range(100001):
    s =  ((i/5000)*'#')+str(i)+(' %')
    print ('\r'+s),

If you are developing a command line interface, I suggest you to take a look at click which is very nice:

import click
import time

for filename in range(3):
    with click.progressbar(range(100), fill_char='=', empty_char=' ') as bar:
        for user in bar:
            time.sleep(0.01)

Here the output you get:

$ python test.py
  [====================================]  100%
  [====================================]  100%
  [=========                           ]   27%

To be pure python and not make system calls:

from time import sleep

for i in range(21):
    spaces = " " * (20 - i)
    percentage = 5*i
    print(f"\r[{'='*i}{spaces}]{percentage}%", flush=True, end="")
    sleep(0.25)