scipy - python: How to construct a sparse matrix out of a 2D-image?

Question

I have a 2D array which represents an image (376, 450) How can I construct a new diagonal matrix (sparse matrix) which has all of the entries of the image along the diagonal and the rest zeroes? When I use for example scipy.sparse.diags I get following error:

ValueError: Different number of diagonals and offsets.

I already checked the documentation here but for me, it is still not quite clear how to do that. Thanks a lot in advance for any tip!

Edit: If I just want to have the entries of the image (2D array) just in the zero-diagonal do I have to flatten the 2D array first into a single dimension?

That I have something like:

from scipy.sparse import diags

new_flat_array = [1,2,3,4, ...]
diags(new_flat_array, [0]).toarray()

But that way the resulting array will not be a sparse 2D matrix which I want.

Answer 1

等待大神答复