[SciPy-user] Sparse matrix: division by vector

Dinesh B Vadhia dineshbvadhia@hotmail....
Tue Apr 29 12:16:38 CDT 2008


Sparse matrix A is in csr_matrix format and I want to divide each column element j of A by A's column j sum (where colSum is a numpy vector) ie.

> A[:,j] = A[:,j]/colSum[j]

What is the most efficient way to achieve this apart from brute force ie. 

> A[i,j] = A[i,j]/colSum[j] ?

I can initially create A in a different c**_matrix method if that helps but the final A has to be in csr_matrix form.

Cheers!

Dinesh
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