Replace all off diagonal elements in numpy array

Question

I have below numpy array

import numpy as np
np.identity(13)

Now I like to replace all off-diagonal elements with some other number, say 0.45.

Is there any direct method available to perform this?

Does this answer your question? In matrix of 100 x 100 in python, filling the off diagonal elements — Renat
– Renat, Commented Dec 6, 2022 at 16:12

SomeDude · Accepted Answer · 2022-12-06 16:26:23Z

2

np.where(np.identity(13)==0, 0.45, 1)

answered Dec 6, 2022 at 16:26

SomeDude

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Comments

andthum · Accepted Answer · 2022-12-06 16:27:30Z

1

What about the following?

import numpy as np
n = 13
val_offdiag = 0.45
val_diag = 1
a = np.full((n ,n), val_offdiag) - np.identity(n) * (val_offdiag - val_diag)

answered Dec 6, 2022 at 16:18

andthum

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