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

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