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Python Numpy - if array is in array

I want to check with most efficiency way (the fastest way), if some array (or list) is in numpy array. But when I do this:

import numpy

a = numpy.array(
    [
        [[1, 2]],
        [[3, 4]]
    ])

print([[3, 5]] in a)

It only compares the first value and returns True

Somebody knows, how can I solve it? Thank you.

question from:https://stackoverflow.com/questions/65922125/python-numpy-if-array-is-in-array

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1 Answer

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by (71.8m points)

Your question seems to be a duplicate of: How to match pairs of values contained in two numpy arrays

In any case, something like the first answer should do it if I understand correctly:

import numpy

a = numpy.array(
    [
        [[1, 2]],
        [[3, 4]]
    ])

b = numpy.array([[3,5]])

print((b[:,None] == a).all(2).any(1))

Which outputs:

array([False,  True])

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