我有一个Python命令行程序,需要一段时间才能完成。我想知道完成跑步所需的确切时间。

我看过timeit模块,但它似乎只适用于小代码片段。我想给整个节目计时。


当前回答

有一个timeit模块,可用于对Python代码的执行时间进行计时。

它在Python文档26.6中有详细的文档和示例。timeit-测量小代码片段的执行时间。

其他回答

我在很多地方都遇到了同样的问题,所以我创建了一个方便的套装占星术。你可以用pip安装钟表,然后以优雅的方式安装:

from horology import Timing

with Timing(name='Important calculations: '):
    prepare()
    do_your_stuff()
    finish_sth()

将输出:

Important calculations: 12.43 ms

或者更简单(如果你有一个功能):

from horology import timed

@timed
def main():
    ...

将输出:

main: 7.12 h

它负责单位和舍入。它适用于python 3.6或更高版本。

time.clock()

自3.3版起已弃用:此函数的行为取决于在平台上:改用perf_counter()或process_time(),这取决于您的需求,以具有定义良好的行为。

time.perf_counter()

返回性能计数器的值(以秒为单位),即具有最高可用分辨率的时钟来测量短路期间它包括睡眠期间的时间系统范围内。

time.process_time()

返回系统和当前进程的用户CPU时间。它不包括经过的时间在睡眠期间。

start = time.process_time()
... do something
elapsed = (time.process_time() - start)

这是获取程序运行时间的最简单方法:

在程序末尾编写以下代码。

import time
print(time.clock())

根据这个答案,创建了一个简单但方便的工具。

import time
from datetime import timedelta

def start_time_measure(message=None):
    if message:
        print(message)
    return time.monotonic()

def end_time_measure(start_time, print_prefix=None):
    end_time = time.monotonic()
    if print_prefix:
        print(print_prefix + str(timedelta(seconds=end_time - start_time)))
    return end_time

用法:

total_start_time = start_time_measure()    
start_time = start_time_measure('Doing something...')
# Do something
end_time_measure(start_time, 'Done in: ')
start_time = start_time_measure('Doing something else...')
# Do something else
end_time_measure(start_time, 'Done in: ')
end_time_measure(total_start_time, 'Total time: ')

输出:

Doing something...
Done in: 0:00:01.218000
Doing something else...
Done in: 0:00:01.313000
Total time: 0:00:02.672000

在Linux或Unix中:

$ time python yourprogram.py

在Windows中,请参阅StackOverflow问题:如何在Windows命令行上测量命令的执行时间?

对于更详细的输出,

$ time -v python yourprogram.py
    Command being timed: "python3 yourprogram.py"
    User time (seconds): 0.08
    System time (seconds): 0.02
    Percent of CPU this job got: 98%
    Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.10
    Average shared text size (kbytes): 0
    Average unshared data size (kbytes): 0
    Average stack size (kbytes): 0
    Average total size (kbytes): 0
    Maximum resident set size (kbytes): 9480
    Average resident set size (kbytes): 0
    Major (requiring I/O) page faults: 0
    Minor (reclaiming a frame) page faults: 1114
    Voluntary context switches: 0
    Involuntary context switches: 22
    Swaps: 0
    File system inputs: 0
    File system outputs: 0
    Socket messages sent: 0
    Socket messages received: 0
    Signals delivered: 0
    Page size (bytes): 4096
    Exit status: 0