It seems like there are missing sparse matrix methods. In both 1.0.2 and 0.7 this code: using SparseArrays using LinearAlgebra A = sprand(10,10,.9) b_dense = Array(sprand(10,1,.8)) # works b_sparse = sprand(10,1,.8) # doesn't work x = A\b_dense # works x = A\b_sparse # doesn't work lu!(A) # gives …

We use the library UMFPACK for solving problems with an asymmetric lhs and unfortunately the library doesn’t support a sparse rhs.

That makes sense, but it seems like the error message could be a bit more user friendly. Also, why does lu!(A) not work for a sparse matrix? The existing error for A\b pointed me to lu!, but lu!() doesn’t work. It seems odd that we can’t factor sparse matrices using the “default” version of lu.

[image] Paul_Hines: Also, why does lu!(A) not work for a sparse matrix? You should use lu(A). lu!(A) means that you want LU factorization in-place, which is not generally possible for sparse matrices.

Missing sparse methods

Specific Domains Numerics

Topic		Replies	Views
Sparse arrays "\" Numerics	2	1626	November 2, 2019
Solving sparse matrix using backslash, got MethodError: no method matching lu! Numerics linearalgebra , sparse	3	1073	July 11, 2020
Julia cannot solve Ax=b with LU where A is sparse, General Usage question , linearalgebra , sparse	12	1298	May 5, 2023
Sparse linear algebra question lu(::SparseMatrixCSC) General Usage linearalgebra , sparse	2	668	June 10, 2021
How to make division for SparceMatrices? General Usage question	2	319	October 18, 2021

Missing sparse methods

Related topics