[issue15438] Incredible issue in math.pow

[Amaury Forgeot d'Arc]

Amaury Forgeot d'Arc <amauryfa at gmail.com> added the comment:

C comparison rules are different from Python's.
In the program below (which outputs 1), the mixed comparison will first convert the literal to a double, and lost some precision.
Python does the opposite: the (imprecise) float is converted to a long, so all digits are compared.


#include <math.h>
#include <stdio.h>
int main()
{
    printf("result: %d\n", (pow(43,10) == 21611482313284249));
}

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nosy: +amaury.forgeotdarc

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<http://bugs.python.org/issue15438>
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