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@pzelnip
Created July 18, 2012 23:20
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Counting number of elements in a list that meet criteria
from timeit import Timer
if __name__ == "__main__":
setup = 'x = list(range(100000))'
num_iter = 1000
print(Timer('sum(1 for item in x if item % 2 == 0)', setup).timeit(num_iter))
print(Timer('len([item for item in x if item % 2 == 0])', setup).timeit(num_iter))
# prints (on my machine):
# 12.4215...
# 10.9932...
# showing that the len() on a list comp is a bit faster.
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