Utility function to extract row and column indices of the non-zero elements of a sparse matrix.
A matrix that is a subclass of sparseMatrix, as defined in the Matrix package.
TRUE if the index of the first element should be 1, and FALSE if 0.
A wrapper to Matrix.to.Pointers for
values=FALSE, for extracting the row and column indices
of a sparsity pattern from a matrix that has that same pattern.
A list with two named elements.
Integer vector containing row indices of non-zero elements
Integer vector containing column indices of non-zero elements
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