Sparse matrix and zero pivots

I have a large sparse matrix and I need to find a position of zero pivots, so my matrix is singular. Standard QR factorization for dense matrices without permutations gives the result that I need, the pivots are on the main diagonal of the matrix R. Because I have a sparse matrix I use SPQR, but then I have permutations of columns and rows and I lose the pivot position. Is there a smart way to find pivots, without converting matrix from sparse to dense?

See In the next version of Julia, it will be possible to disable pivoting in the sparse QR.

Notice that zero pivots don’t imply singularity, e.g.

[0 1
 1 1]
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thank you, regarding the note, I agree with you :smiley: