Python Progress Bar

Question

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.

Answer 1

Answer 2

I like this page.

Starts with simple example and moves onto a multi-threaded version. Works out of the box. No 3rd party packages required.

The code will look something like this:

import time
import sys

def do_task():
    time.sleep(1)

def example_1(n):
    for i in range(n):
        do_task()
        print '\b.',
        sys.stdout.flush()
    print ' Done!'

print 'Starting ',
example_1(10)

Or here is example to use threads in order to run the spinning loading bar while the program is running:

import sys
import time
import threading

class progress_bar_loading(threading.Thread):

    def run(self):
            global stop
            global kill
            print 'Loading....  ',
            sys.stdout.flush()
            i = 0
            while stop != True:
                    if (i%4) == 0: 
                        sys.stdout.write('\b/')
                    elif (i%4) == 1: 
                        sys.stdout.write('\b-')
                    elif (i%4) == 2: 
                        sys.stdout.write('\b\\')
                    elif (i%4) == 3: 
                        sys.stdout.write('\b|')

                    sys.stdout.flush()
                    time.sleep(0.2)
                    i+=1

            if kill == True: 
                print '\b\b\b\b ABORT!',
            else: 
                print '\b\b done!',


kill = False      
stop = False
p = progress_bar_loading()
p.start()

try:
    #anything you want to run. 
    time.sleep(1)
    stop = True
except KeyboardInterrupt or EOFError:
         kill = True
         stop = True

Answer 3

The code below is a quite general solution and also has a time elapsed and time remaining estimate. You can use any iterable with it. The progress bar has a fixed size of 25 characters but it can show updates in 1% steps using full, half, and quarter block characters. The output looks like this:

 18% |████▌                    | [0:00:01, 0:00:07]

Code with example:

import sys, time
from numpy import linspace

def ProgressBar(iterObj, refreshTime=10):
  #refreshTime=10: refresh the time estimate at least every 10 sec.
  def SecToStr(sec):
    m, s = divmod(sec, 60)
    h, m = divmod(m,   60)
    return u'%d:%02d:%02d'%(h,m,s)
  L       = len(iterObj)
  steps   = {int(x):y for x,y in zip(np.linspace(0,L,  min(100,L),endpoint=False), 
                                     np.linspace(0,100,min(100,L),endpoint=False))}
  qSteps  = ['', u'\u258E',u'\u258C',u'\u258A'] # quarter and half block chars
  startT  = endT = time.time()
  timeStr = ' [0:00:00, -:--:--]'
  for nn,item in enumerate(iterObj):
    if nn in steps:
      done    = u'\u2588'*int(steps[nn]/4.0)+qSteps[int(steps[nn]%4)]
      todo    = ' '*(25-len(done))
      barStr  = u'%4d%% |%s%s|'%(steps[nn], done, todo)
      if nn>0:
        endT    = time.time()
        timeStr = ' [%s, %s]'%(SecToStr(endT-startT), SecToStr((endT-startT)*(L/float(nn)-1)))
      sys.stdout.write('\r'+barStr+timeStr); sys.stdout.flush()
    elif time.time()-endT > refreshTime:
      endT    = time.time()
      timeStr = ' [%s, %s]'%(SecToStr(endT-startT), SecToStr((endT-startT)*(L/float(nn)-1)))
      sys.stdout.write('\r'+barStr+timeStr); sys.stdout.flush()
    yield item
  barStr  = u'%4d%% |%s|'%(100, u'\u2588'*25)
  timeStr = ' [%s, 0:00:00]\n'%(SecToStr(time.time()-startT))
  sys.stdout.write('\r'+barStr+timeStr); sys.stdout.flush()

# Example
s = ''
for op in ProgressBar(list('Disassemble and reassemble this string')):
  time.sleep(0.5)
  s += op
print s

Suggestions for improvements or other comments are welcome. Have fun.

Answer 4

With tqdm you can add a progress meter to your loops in a second:

In [20]: import time

In [21]: from tqdm import tqdm

In [23]: for i in tqdm(range(10)):
   ....:     time.sleep(3)

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

Answer 5

I've just made a simple progress class for my needs after searching here for a equivalent solution. I thought I might a well post it.

from __future__ import print_function
import sys
import re


class ProgressBar(object):
    DEFAULT = 'Progress: %(bar)s %(percent)3d%%'
    FULL = '%(bar)s %(current)d/%(total)d (%(percent)3d%%) %(remaining)d to go'

    def __init__(self, total, width=40, fmt=DEFAULT, symbol='=',
                 output=sys.stderr):
        assert len(symbol) == 1

        self.total = total
        self.width = width
        self.symbol = symbol
        self.output = output
        self.fmt = re.sub(r'(?P<name>%\(.+?\))d',
            r'\g<name>%dd' % len(str(total)), fmt)

        self.current = 0

    def __call__(self):
        percent = self.current / float(self.total)
        size = int(self.width * percent)
        remaining = self.total - self.current
        bar = '[' + self.symbol * size + ' ' * (self.width - size) + ']'

        args = {
            'total': self.total,
            'bar': bar,
            'current': self.current,
            'percent': percent * 100,
            'remaining': remaining
        }
        print('\r' + self.fmt % args, file=self.output, end='')

    def done(self):
        self.current = self.total
        self()
        print('', file=self.output)

---

Example :

from time import sleep

progress = ProgressBar(80, fmt=ProgressBar.FULL)

for x in xrange(progress.total):
    progress.current += 1
    progress()
    sleep(0.1)
progress.done()

Will print the following:

[======== ] 17/80 ( 21%) 63 to go

Answer 6

I like Brian Khuu's answer for its simplicity and not needing external packages. I changed it a bit so I'm adding my version here:

import sys
import time


def updt(total, progress):
    """
    Displays or updates a console progress bar.

    Original source: https://stackoverflow.com/a/15860757/1391441
    """
    barLength, status = 20, ""
    progress = float(progress) / float(total)
    if progress >= 1.:
        progress, status = 1, "\r\n"
    block = int(round(barLength * progress))
    text = "\r[{}] {:.0f}% {}".format(
        "#" * block + "-" * (barLength - block), round(progress * 100, 0),
        status)
    sys.stdout.write(text)
    sys.stdout.flush()


runs = 300
for run_num in range(runs):
    time.sleep(.1)
    updt(runs, run_num + 1)

It takes the total number of runs (total) and the number of runs processed so far (progress) assuming total >= progress. The result looks like this:

[#####---------------] 27%