Script to show progress?

问题:

I would like show progress to user when my python script processing a big file.

I have seen script printings '\', "|', '/' in the same cursor position in the shell to show progress.

How can I do that in python?

回答1:

A simple "infinite spinner" implementation:

import time
import itertools

for c in itertools.cycle('/-\|'):
    print(c, end = '\r')
    time.sleep(0.2)

回答2:

You should use python-progressbar

It's as simple to use as:

import progressbar as pb

progress = pb.ProgressBar(widgets=_widgets, maxval = 500000).start()
progvar = 0

for i in range(500000):  
    # Your code here
    progress.update(progvar + 1)
    progvar += 1

This will show a progress bar like:

Progress: |####################################################            |70%

回答3:

tqdm is a more powerful one for this case. it has better features and comparability.

it is easy for usage, the code could be simple as:

from tqdm import tqdm
for i in tqdm(range(10000)):
    pass  # or do something else

customization is also easy for special cases.

here is a demo from the repo:

回答4:

If you want to roll your own, you can do something like this:

import sys, time

for i in range(10):
  print ".", # <- no newline
  sys.stdout.flush() #<- makes python print it anyway
  time.sleep(1)

print "done!"

This'll print one dot every second and then print "done!"

回答5:

Or the usual helicopter (in Python 3):

import sys, time

for i in range(10):
   print("/-\|"[i % 4], end="\b")
   sys.stdout.flush()  #<- makes python print it anyway
   time.sleep(0.1)

print("\ndone!")

回答6:

Made this for fun. It shows the spinning bar and the text loading. Like this:

|         
\ l       
- lo      
/ loa     
| load    
\ loadi   
- loadin  
/ loading 

The code was tested on windows.

'''
Spinner and a text showing loading.
'''
import sys
import time

def looper(text):
    sys.stdout.write('\r')
    sys.stdout.write(text)
    sys.stdout.flush()

spinner = ["|", "\\" , "-", "/" ]
loading = ['l','o','a','d','i','n','g']

spin_1 = len(spinner)
spin_2 = len(loading) + 1

print("Starting program...")

for x in range(100):
    spin_2mod = x%spin_2
    looper(spinner[x%spin_1] + " " + "".join(loading[0: (spin_2mod) ]) + (" " * (spin_2 - spin_2mod)))
    time.sleep(0.5)

print("\nExiting program...")
time.sleep(2)

回答7:

This code works for me:

class ProgressBar(object):

  def __init__(self, maxval=100):
    self.currval = 0
    self.maxval = int(maxval)
    self.last_progress = 0
    sys.stdout.write("0")
    sys.stdout.flush()

  def next(self, val = None):
    if val:
        self.currval = val
    else:
        self.currval = self.currval + 1
    progress = round(20 * self.currval / self.maxval)

    while self.last_progress < progress:
        self.last_progress = self.last_progress + 1
        self._print_progress(self.last_progress)

  def finish(self):
    while self.last_progress < 20:
        self.last_progress = self.last_progress + 1
        self._print_progress(self.last_progress)
    sys.stdout.write("\n")
    sys.stdout.flush()

  def _print_progress(self, progress):
    if progress % 5 == 0:
        percent = int(progress * 5)
        sys.stdout.write(str(percent))
    else:
        sys.stdout.write(".")
    sys.stdout.flush()

This code works well with large amount of iterations like hundreds of millions - it doesn't redraw console on every iteration.

Use sample:

progress = ProgressBar(band.YSize)
for y in xrange(0, band.YSize, 256):    
    array = band.ReadAsArray(x, y, 256, 256)
    map_array_values(array, values)
    progress.next(y)
    del array
progress.finish()

It will display progress in GDAL style: