python 2.7 - Extratcing all square submatrices from matrix using Numpy -

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say have nxn numpy matrix. looking fastest way of extracting square chunks (sub-matrices) matrix. meaning cxc parts of original matrix 0 < c < n+1. sub-matrices should correspond contiguous rows/columns indexes of original matrix. want achieve in little time possible.

you use numpy slicing,

import numpy np  n = 20 x = np.random.rand(n, n)  slice_list = [slice(k, l) k in range(0, n) l in range(k, n)]  results = [x[sl,sl] sl in slice_list]

avoiding loops in numpy, not goal itself. long being mindful it, there shouldn't overhead.


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