all Python 3timeitfunction

timeit.timeit()

timing

Runs a code snippet number times and returns the total time in seconds, for benchmarking.

Syntax

timeit.timeit(stmt='pass', setup='pass', timer=default_timer, number=1000000, globals=None) -> float

The result is the total time for all runs, not one: the default number is 1,000,000, so timing slow code seems to hang. Code given as a string cannot see your variables; pass setup='from __main__ import f' or globals=globals(), or pass a zero-argument callable. Garbage collection is disabled while timing, so numbers can be more optimistic than reality.

Examples

import timeit
t = timeit.timeit('sum(range(100))', number=1000)
print(type(t).__name__)  # → float
print(t)  # → ? время зависит от машины

import timeit
data = list(range(100))
t = timeit.timeit('sorted(data)', globals={'data': data}, number=100)
print(t > 0)  # → True
timeit.timeit('sorted(data)', number=1)  # → NameError: name 'data' is not defined

See also

Common errors

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