Jean, You can use -ksp_use_explicittranspose to make KSP transpose the system explicitly in the transposed solve. This option was designed to enable more choices of linear solvers and preconditions in adjoint solves, of course, at a cost.
Hong (Mr.) On Apr 8, 2022, at 4:52 PM, Jean Marques <[email protected]<mailto:[email protected]>> wrote: Hi all, This may be a naive question, and I hope this is the right place to ask about it. I need to solve a direct linear system with a sparse matrix R, then an adjoint system the hermitian of R. I use a petsc4py, so what I do is this: self.R.setUp() to set up the PETSc KSP variable R, then I do: self.R.solve(f, q) and later: self.R.solveTranspose(f, q) However, 'solveTranspose()' only works when I use MUMPS. If I try STRUMPACK or SUPERLU_DIST it fails, it seems that 'solveTranpose()' is not defined for them? or is there a specific way to call them with these libraries? Maybe the approach would be to define another 'self.R' variable but then set it as a transpose().conjugate() before setUp()? I was trying STRUMPACK because it has a low-memory approach and that's my main bottleneck. I appreciate any help you can provide. Best, Jean -- Jean Helder Marques Ribeiro Ph.D. Candidate University of California, Los Angeles 420 Westwood Plaza, Los Angeles, CA 90095 phone: (310) 689-6593
