Hi Barry, I am trying to port this preconditioner I found presented at the last PETSc conference into may code: https://urldefense.us/v3/__https://github.com/ndjinga/SOLVERLAB/blob/master/CoreFlows/examples/C/SaddlePointPreconditioner/SaddlePointLinearSolver.c__;!!G_uCfscf7eWS!a-JnrBsta75n_WDtxUNd7Xb8_m7tg1pWSxwWNTmUBSfpBwISq4IxJkbM6QgADd-x23Q_2s-d6d6bOWCKGRMxMzHyc9DDm7A$
So far so good, I am just translating C to Fortran, however when I try to solve my linear system with: call KSPSetOperators(ksp, Ahat, Pmat, ierr) call KSPSolve(ksp, bhat, xhat, ierr) with Ahat and Pmat being indeed two nest MatNest, created from an array of Mat as: call MatCreateNest(PETSC_COMM_WORLD, 2, PETSC_NULL_IS, 2, PETSC_NULL_IS, Mat_array, Ahat, ierr) call MatCreateNest(PETSC_COMM_WORLD, 2, PETSC_NULL_IS, 2, PETSC_NULL_IS, Mat_array, Pmat, ierr) However I am getting this error on getinfo: from C to Fortran [0]PETSC ERROR: --------------------- Error Message -------------------------------------------------------------- [0]PETSC ERROR: No support for this operation for this object type [0]PETSC ERROR: No method getinfo for Mat of type nest [0]PETSC ERROR: See https://urldefense.us/v3/__https://petsc.org/release/faq/__;!!G_uCfscf7eWS!a-JnrBsta75n_WDtxUNd7Xb8_m7tg1pWSxwWNTmUBSfpBwISq4IxJkbM6QgADd-x23Q_2s-d6d6bOWCKGRMxMzHyRUMnyvE$ for trouble shooting. [0]PETSC ERROR: Petsc Release Version 3.20.4, unknown How can I get rid of this issue? Many thanks!
