Say Mat A =[[UU, UP', UA'], [UP, 0, 0], [UA, 0, 0]]; Mat P=[[UU, 0, 0], [0, PP, 0], [0, 0, AA]]; How can we apply P as the preconditioner for solving Ax = f in FreeFem using syntax like set(A , sparams = " ... ", fields = usPETSc, names = names); x = A^-1 …

Specify a block preconditioner? KSPSetOperators(KSP ksp, Mat Amat, Mat Pmat)

prj June 30, 2023, 5:21am 2

Topic		Replies	Views
Applying a modified preconditioner matrix in PETSc General Discussion	4	709	August 6, 2021
Is it possible to set PCD preconditioner within schurPreconditioner General Discussion	3	30	February 27, 2026
Preconditioner for PETSc Mat General Discussion	7	647	July 18, 2021
About the interface to petsc Feature Request	2	887	May 8, 2019
Adding MatDiagonalSet, MatAXPY and MatAYPX Feature Request	37	2674	January 28, 2022