SparseArrays.jl icon indicating copy to clipboard operation
SparseArrays.jl copied to clipboard

Published 20 hours ago • verified publisher icon JuliaSparse

missing qr(A)' \ b for sparse

Open stevengj opened this issue 5 years ago • 0 comments

If A is a sparse matrix, then we get

julia> qr(A)' \ c
ERROR: MethodError: no method matching adjoint(::SuiteSparse.SPQR.QRSparse{Float64,Int64})

It would be nice to have this implemented.

For example, when minimizing image (least-square + affine), as discussed on discourse, you need to solve systems with both A and A' so it would be nice to easily re-use the QR factorization.

Another missing method is qr(A'). A workaround is to use qr(oftype(A, A')), but that's a bit annoying.

stevengj avatar Apr 10 '20 01:04 stevengj