Indicator array of whether value is contained in another numpy array?

Question

How do I code which items in array 1 are contained within array 2, and append a row reflecting this (1 = it is contained, 0 = it is not:

import numpy as np
array1 = np.array([1,2,3,4,5,10,12,13])

array2 = np.array([4,6,3,5,0])

Expected Result:

np.array([[1,2,3,4,5,10,12,13],
           [0,0,1,1,1,0,0,0]])

yatu · Accepted Answer · 2020-07-30 09:01:50Z

1

Use np.isin and cast the result to integer, the solution is within the previous answer :)

np.vstack([array1, np.isin(array1, array2).view('i1')])
array([[ 1,  2,  3,  4,  5, 10, 12, 13],
       [ 0,  0,  1,  1,  1,  0,  0,  0]])

answered Jul 30, 2020 at 9:01

yatu

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