Changing the values of a matrix above a threshold in python

Question

I have a matrix :

matrix = np.array([[[0,0.5,0.6],[0.9,1.2,0]],[[0,0.5,0.6],[0.9,1.2,0]]])

I want to replace all the values 0.55 < x < 0.95 by 0.55.

PS : My question is similar to this question. But the answer does not work in my case.

Answer 1

You can use np.where:

matrix = np.array([[[0,0.5,0.6],[0.9,1.2,0]],[[0,0.5,0.6],[0.9,1.2,0]]])
matrix[np.where((matrix > 0.55) & (matrix < 0.95))] = 0.55
# Or
# matrix[(matrix > 0.55) & (matrix < 0.95)] = 0.55

Output:

>>> matrix
array([[[0.  , 0.5 , 0.55],
        [0.55, 1.2 , 0.  ]],

       [[0.  , 0.5 , 0.55],
        [0.55, 1.2 , 0.  ]]])