## Python and Numpy integers

### March 30, 2009

I keep getting bitten on the bum with Python and ‘proper’ programming things. Today it’s this:

In [253]: 8**14 Out[253]: 4398046511104L In [254]: 8**(numpy.int32(14)) Out[254]: 0I would feel guilty about this if I had to specify the type of numbers I was using, but this is a dynamic programming language! How the hell am I supposed to know that raising an int by a numpy.int32 will force the result to also be an numpy.int32 (and therefore (silently) 0 because int32 can’t hold my number) whereas raising an int by an int will result in a long? Why didn’t the int32 become a long also? Or an int64 or something that could hold my number?

Gah!

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