Extract submatrix at certain row/col values

Question

I need to slice a 2D input array from row/col indices and a slicing distance. In my example below, I can extract a 3x3 submatrix from an input matrix, but I cannot adapt this co

Answer 1

Numpy has matrix slicing, so you can slice on both rows and columns.

mat_A[4:7, 4:7]

returns

  [[44, 45, 46],
   [54, 55, 56],
   [64, 65, 66]]

Answer 2

S=3 # window "radius"; S=3 gives a 5x5 submatrix
mat_A[row-S+1:row+S,col-S+1:col+S]
#array([[33, 34, 35, 36, 37],
#       [43, 44, 45, 46, 47],
#       [53, 54, 55, 56, 57],
#       [63, 64, 65, 66, 67],
#       [73, 74, 75, 76, 77]])