I'd like to get a right null vector of a large, sparse matrix. My plan is to use SPQR (although I'm happy to consider alternatives). The documentation for SPQR states that if QR factorization is applied to a matrix that does not have full column rank, then a 'squeezed' R factor is computed from which a right null vector can be deduced.
However, as far as I can see, the Julia interface to SPQR in base/sparse/spqr.jl (Julia version 0.4.6) does not provide access to any of the factors but only yields an opaque handle to a C data structure. Could someone give me a clue how to get access to the R factor of the QR factorization computed by SPQR? Ideally I would obtain R as a SparseMatrixCSC object. Thanks, Steve Vavasis
