Is there a NumPy method to change a range of values in a 2d array?

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I would like to change a range of values in a 2d NumPy array in a simple way. For example, imagine I have a 2d array of shape (5,5). If I want to change the values of the upper 2x2 'block', I can use the NumPy put function. This is an example:

import numpy as np

A = np.zeros(shape=(5,5))
np.put(A, [[0,1,2,5,6,7,10,11,12]], 1)

Resulting in:

print(A)
[[1. 1. 1. 0. 0.]
 [1. 1. 1. 0. 0.]
 [1. 1. 1. 0. 0.]
 [0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0.]]

Ideally, however, I would like to do the following: use the coordinates of a square to directly change a range of values, without flattening the array. In the example, these coordinates would be [(0,0), (2,2)]. Is there a Pythonic way of doing this?

numpy-ndarray numpy python
1 Answers

IIUC, you can try:

cor = [(1,1), (2,2)]
(x1,y1),(x2,y2) = cor
a[x1:x2+1, y1:y2+1] =1

OUTPUT:

array([[0., 0., 0., 0., 0.],
       [0., 1., 1., 0., 0.],
       [0., 1., 1., 0., 0.],
       [0., 0., 0., 0., 0.],
       [0., 0., 0., 0., 0.]])
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