当您从命令行这样调用timeit
时:
python -mtimeit -s'import test' 'test.foo()'
timeit
模块称为脚本。特别地,main
函数称为:
if __name__ == "__main__":
sys.exit(main())
[如果您查看the source code,您会发现main
函数可以采用args
参数:
def main(args=None):
if args is None:
args = sys.argv[1:]
因此,确实可以从程序中运行timeit
,其行为与从CLI运行时完全相同。只需提供自己的args
,而不是将其设置为sys.argv[1:]
:
import timeit
import shlex
def foo():
total = 0
for i in range(10000):
total += i**3
return total
timeit.main(args=shlex.split("""-s'from __main__ import foo' 'foo()'"""))
将打印类似内容
100 loops, best of 3: 7.9 msec per loop
[不幸的是,main
打印到控制台,而不是返回每个循环的时间。因此,如果要以编程方式使用结果,也许最简单的方法是从复制the main
function开始然后对其进行修改-更改打印代码以改为返回main
。
OP的示例:如果将此放置在usec
中:
utils_timeit.py
您可以在这样的脚本中使用它:
import timeit
def timeit_auto(stmt="pass", setup="pass", repeat=3):
"""
http://stackoverflow.com/q/19062202/190597 (endolith)
Imitate default behavior when timeit is run as a script.
Runs enough loops so that total execution time is greater than 0.2 sec,
and then repeats that 3 times and keeps the lowest value.
Returns the number of loops and the time for each loop in microseconds
"""
t = timeit.Timer(stmt, setup)
# determine number so that 0.2 <= total time < 2.0
for i in range(1, 10):
number = 10**i
x = t.timeit(number) # seconds
if x >= 0.2:
break
r = t.repeat(repeat, number)
best = min(r)
usec = best * 1e6 / number
return number, usec
从Python 3.6开始,import timeit
import utils_timeit as UT
def foo():
total = 0
for i in range(10000):
total += i**3
return total
num, timing = UT.timeit_auto(setup='from __main__ import foo', stmt='foo()')
print(num, timing)
对象具有timeit.Timer
函数,该函数公开如何确定timeit.Timer
用于命令行执行。