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

对于类似的应用程序(在循环中跟踪进度),我简单地使用python-progressbar:

他们的例子是这样的,

from progressbar import *               # just a simple progress bar


widgets = ['Test: ', Percentage(), ' ', Bar(marker='0',left='[',right=']'),
           ' ', ETA(), ' ', FileTransferSpeed()] #see docs for other options

pbar = ProgressBar(widgets=widgets, maxval=500)
pbar.start()

for i in range(100,500+1,50):
    # here do something long at each iteration
    pbar.update(i) #this adds a little symbol at each iteration
pbar.finish()
print

其他回答

没有外部包。一段现成的代码。

您可以自定义进度条符号“#”,进度条大小,文本前缀等。

Python 3.3 +

import sys
def progressbar(it, prefix="", size=60, out=sys.stdout): # Python3.3+
    count = len(it)
    def show(j):
        x = int(size*j/count)
        print("{}[{}{}] {}/{}".format(prefix, "#"*x, "."*(size-x), j, count), 
                end='\r', file=out, flush=True)
    show(0)
    for i, item in enumerate(it):
        yield item
        show(i+1)
    print("\n", flush=True, file=out)

用法:

import time    
for i in progressbar(range(15), "Computing: ", 40):
    time.sleep(0.1) # any code you need

要填满整个字符空间,请使用unicode u"█"字符替换"#"。使用for i in progressbar(range(100)):…你会得到:

不需要第二个线程。上面的一些解决方案/包需要。 适用于任何可迭代对象,它指的是任何可以使用len()的对象。一个列表,一个字典,比如[' A ', 'b', 'c'…' g '] 使用生成器的工作只需要用list()来包装它。例如,对于i in progressbar(list(your_generator), "Computing: ", 40):除非工作在生成器中完成。在这种情况下,您需要另一种解决方案(如tqdm)。

您还可以通过将out更改为sys来更改输出。例如Stderr。


Python 3.6+ (f-string)

def progressbar(it, prefix="", size=60, out=sys.stdout): # Python3.6+
    count = len(it)
    def show(j):
        x = int(size*j/count)
        print(f"{prefix}[{u'█'*x}{('.'*(size-x))}] {j}/{count}", end='\r', file=out, flush=True)
    show(0)
    for i, item in enumerate(it):
        yield item
        show(i+1)
    print("\n", flush=True, file=out)

Python 2 (old-code)

import sys
def progressbar(it, prefix="", size=60, out=sys.stdout):
    count = len(it)
    def show(j):
        x = int(size*j/count)
        out.write("%s[%s%s] %i/%i\r" % (prefix, u"#"*x, "."*(size-x), j, count))
        out.flush()        
    show(0)
    for i, item in enumerate(it):
        yield item
        show(i+1)
    out.write("\n")
    out.flush()

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

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

使用进度库!

pip install progress

下面是我编写的一个自定义子类,用于将ETA/流逝时间格式化为更好读的格式:

import datetime
from progress.bar import IncrementalBar


class ProgressBar(IncrementalBar):
    '''
    My custom progress bar that:
       - Show %, count, elapsed, eta
       - Time is shown in H:M:S format
    '''

    message = 'Progress'
    suffix  = '%(percent).1f%% (%(index)d/%(max)d) -- %(elapsed_min)s (eta: %(eta_min)s)'

    def formatTime(self, seconds):
        return str(datetime.timedelta(seconds=seconds))

    @property
    def elapsed_min(self):
        return self.formatTime(self.elapsed)

    @property
    def eta_min(self):
        return self.formatTime(self.eta)

if __name__=='__main__':
    counter = 120
    bar     = ProgressBar('Processing', max=counter)

    for i in range(counter):
        bar.next()
        time.sleep(1)

    bar.finish()