How to identify numpy types in python?

python numpy duck-typing dynamic-typing
Douglas B. Staple picture Douglas B. Staple · Sep 24, 2012 · Viewed 118.3k times · Source

How can one reliably determine if an object has a numpy type?

I realize that this question goes against the philosophy of duck typing, but idea is to make sure a function (which uses scipy and numpy) never returns a numpy type unless it is called with a numpy type. This comes up in the solution to another question, but I think the general problem of determining if an object has a numpy type is far enough away from that original question that they should be separated.

Answer

abarnert picture abarnert · Sep 24, 2012

Use the builtin type function to get the type, then you can use the __module__ property to find out where it was defined:

>>> import numpy as np
a = np.array([1, 2, 3])
>>> type(a)
<type 'numpy.ndarray'>
>>> type(a).__module__
'numpy'
>>> type(a).__module__ == np.__name__
True

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