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。
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
我认为这是最好和最简单的方法:
from time import monotonic
start_time = monotonic()
# something
print(f"Run time {monotonic() - start_time} seconds")
或与装饰师一起:
from time import monotonic
def record_time(function):
def wrap(*args, **kwargs):
start_time = monotonic()
function_return = function(*args, **kwargs)
print(f"Run time {monotonic() - start_time} seconds")
return function_return
return wrap
@record_time
def your_function():
# something
其他回答
我定义了以下Python装饰器:
def profile(fct):
def wrapper(*args, **kw):
start_time = time.time()
ret = fct(*args, **kw)
print("{} {} {} return {} in {} seconds".format(args[0].__class__.__name__,
args[0].__class__.__module__,
fct.__name__,
ret,
time.time() - start_time))
return ret
return wrapper
并将其用于函数或类/方法:
@profile
def main()
...
我将这个timing.py模块放入我自己的站点包目录中,并在模块顶部插入导入计时:
import atexit
from time import clock
def secondsToStr(t):
return "%d:%02d:%02d.%03d" % \
reduce(lambda ll,b : divmod(ll[0],b) + ll[1:],
[(t*1000,),1000,60,60])
line = "="*40
def log(s, elapsed=None):
print line
print secondsToStr(clock()), '-', s
if elapsed:
print "Elapsed time:", elapsed
print line
print
def endlog():
end = clock()
elapsed = end-start
log("End Program", secondsToStr(elapsed))
def now():
return secondsToStr(clock())
start = clock()
atexit.register(endlog)
log("Start Program")
如果程序中有重要的阶段,我也可以在程序中调用timing.log。但仅包括导入计时就可以打印开始和结束时间,以及总运行时间。(请原谅我晦涩难懂的secondsToStr函数,它只是将浮点秒数设置为hh:mm:ss.sss格式。)
注意:上述代码的Python3版本可以在这里找到。
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)
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
使用line_profiler。
line_profiler将描述单个代码行执行所需的时间。分析器通过Cython在C语言中实现,以减少分析开销。
from line_profiler import LineProfiler
import random
def do_stuff(numbers):
s = sum(numbers)
l = [numbers[i]/43 for i in range(len(numbers))]
m = ['hello'+str(numbers[i]) for i in range(len(numbers))]
numbers = [random.randint(1,100) for i in range(1000)]
lp = LineProfiler()
lp_wrapper = lp(do_stuff)
lp_wrapper(numbers)
lp.print_stats()
结果将是:
Timer unit: 1e-06 s
Total time: 0.000649 s
File: <ipython-input-2-2e060b054fea>
Function: do_stuff at line 4
Line # Hits Time Per Hit % Time Line Contents
==============================================================
4 def do_stuff(numbers):
5 1 10 10.0 1.5 s = sum(numbers)
6 1 186 186.0 28.7 l = [numbers[i]/43 for i in range(len(numbers))]
7 1 453 453.0 69.8 m = ['hello'+str(numbers[i]) for i in range(len(numbers))]