当我的脚本正在执行一些可能需要时间的任务时,我如何使用进度条?

例如,一个函数需要一段时间才能完成,完成后返回True。如何在函数执行期间显示进度条?

请注意,我需要这是实时的,所以我不知道该怎么做。我需要一根线吗?我不知道。

现在我没有打印任何东西,而函数正在执行,但一个进度条会很好。此外,我更感兴趣的是从代码的角度如何做到这一点。


当前回答

上面的建议非常好,但我认为大多数人只是想要一个现成的解决方案,不依赖于外部包,但也是可重用的。

我得到了上面所有的优点,并把它做成了一个函数,以及一个测试用例。

要使用它,只需复制“def update_progress(progress)”下面的行,而不是测试脚本。不要忘记导入sys。在需要显示或更新进度条时调用此函数。

这是通过直接向控制台发送“\r”符号来将光标移回起始位置。python中的"print"不能识别上述符号,因此我们需要'sys'

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 = 10 # 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()


# update_progress test script
print "progress : 'hello'"
update_progress("hello")
time.sleep(1)

print "progress : 3"
update_progress(3)
time.sleep(1)

print "progress : [23]"
update_progress([23])
time.sleep(1)

print ""
print "progress : -10"
update_progress(-10)
time.sleep(2)

print ""
print "progress : 10"
update_progress(10)
time.sleep(2)

print ""
print "progress : 0->1"
for i in range(101):
    time.sleep(0.1)
    update_progress(i/100.0)

print ""
print "Test completed"
time.sleep(10)

这是测试脚本显示的结果(最后一个进度条是动画):

progress : 'hello'
Percent: [----------] 0% error: progress var must be float
progress : 3
Percent: [##########] 100% Done...
progress : [23]
Percent: [----------] 0% error: progress var must be float

progress : -10
Percent: [----------] 0% Halt...

progress : 10
Percent: [##########] 100% Done...

progress : 0->1
Percent: [##########] 100% Done...
Test completed

其他回答

有一些特定的库(比如这里的这个),但也许一些非常简单的库就可以做到:

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 range(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

注意:progressbar2是progressbar的一个分支,已经很多年没有维护过了。

这是创建进度条的简单方法

import time,sys
toolbar_width = 50
# setting up toolbar [-------------------------------------]
sys.stdout.write("[%s]"%(("-")*toolbar_width))
sys.stdout.flush()
# each hash represents 2 % of the progress
for i in range(toolbar_width):
    sys.stdout.write("\r") # return to start of line
    sys.stdout.flush()
    sys.stdout.write("[")#Overwrite over the existing text from the start 
    sys.stdout.write("#"*(i+1))# number of # denotes the progress completed 
    sys.stdout.flush()
    time.sleep(0.1)
#doesnt affect actual execution
#based on events and consumption in background
#may be that actual process completes a bit earlier than progress shows 99%
#make an instance with number of elements in a loop
#in each iteration call the method current_progress

import time
from math import ceil
import os
import sys
from threading import Thread
class progress_bar(object):
 def __init__(self,total_elements,length_bar=25):
  self.length_bar=length_bar
  self.total_elements=total_elements
  self.singleweight=(float(1)/float(total_elements))*100
  self.done=0
  self.qt=[0]
  self.call_count=0
  t=Thread(target=self.display_progress)
  t.start()
 def current_progress(self):
  self.done+=1
  self.qt=[self.done]+self.qt
 def display_progress(self):
  while True:
   try:
    done=self.qt.pop()
   except:
    continue
   else:
    self.call_count+=1
    self.progress=self.singleweight*done
    fill=ceil(self.progress)
    bar=int((fill*self.length_bar)/100)*"|"
    bar="["+bar+str(fill)+"%"
    barp=bar
    for i in range(0,self.length_bar+3-(len(bar))):
     barp=barp+"_"
    barp=barp+"]"
    if self.progress <= 100:
     os.system("clear")
     print("Progress:",barp, sep=' ', end='\n', file=sys.stdout, flush=True)
    if self.call_count == self.total_elements:
     break
  else:
   pass

在这里寻找等效的解决方案后,我只是为我的需求做了一个简单的进度类。我想我应该把它贴出来。

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)

例子:

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()

将打印以下内容:

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

当在jupyter笔记本上运行时,使用普通的tqdm无法工作,因为它将输出写在多行上。用这个代替:

import time
from tqdm import tqdm_notebook as tqdm

for i in tqdm(range(100))
    time.sleep(0.5)