Replace occurences of a numpy array in another numpy array with a value

Question

I have a 2D numpy array:

[[1,2,3,4,5],[2,4,5,6,7],[0,9,3,2,4]]

I also have a second 1D array:

[2,3,4]

I want to replace all occurences of the elements of the second array with 0 So eventually, my second array should look like

[[1,0,0,0,5],[0,0,5,6,7],[0,9,0,0,0]]

is there a way in python/numpy I can do this without using a loop.

I already checked at np.where, but the condition there is only for example where element = 1 value, and not multiple.

Thanks a lot !

timgeb · Accepted Answer · 2021-12-14 13:01:33Z

3

Use numpy.isin.

>>> import numpy as np
>>> a = np.array([[1,2,3,4,5],[2,4,5,6,7],[0,9,3,2,4]])
>>> b = np.array([2,3,4])
>>> a[np.isin(a, b)] = 0
>>> a 
array([[1, 0, 0, 0, 5],
       [0, 0, 5, 6, 7],
       [0, 9, 0, 0, 0]])

answered Dec 14, 2021 at 13:01

timgeb

79.2k20 gold badges129 silver badges150 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Replace occurences of a numpy array in another numpy array with a value

1 Answer 1

Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Related