Why is casting from a string to float faster than string to int?

Asked Mar 21 '18 at 14:33

Active Mar 21 '18 at 14:42

Viewed 31 times

Something surprising I just discovered:

>>> def f():
...  float('1')
...
>>> def i():
...  int('1')
...
>>> timeit(f, number=1000000)
0.22292590141296387
>>> timeit(i, number=1000000)
0.4127480983734131

I repeated this many times. float always performs substantially better than int. Why is this happening? What goes on behind the scenes?

edited Mar 21 '18 at 14:42

martineau

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asked Mar 21 '18 at 14:33

ewok

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Just tested `%timeit float('1')` and `%timeit int('1')` in IPython (3) and got opposite results, `int` somewhat faster than `float`... – jdehesa Mar 21 '18 at 14:37

Why is casting from a string to float faster than string to int?

0 Answers0