PETSc version 3.16.5
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# PCASMGetLocalSubmatrices

Gets the local submatrices (for this processor only) for the additive Schwarz preconditioner.

### Synopsis

    #include "petscpc.h"
    PetscErrorCode  PCASMGetLocalSubmatrices(PC pc,PetscInt *n,Mat *mat[])

Not Collective

### Input Parameter

| pc | - the preconditioner context

### Output Parameters

| n | - if requested, the number of matrices for this processor (default value = 1)
| mat | - if requested, the matrices

### Notes

Call after PCSetUp() (or KSPSetUp()) but before PCApply() and before PCSetUpOnBlocks())

Usually one would use PCSetModifySubMatrices() to change the submatrices in building the preconditioner.

### See Also

PCASMSetTotalSubdomains(), PCASMSetOverlap(), PCASMGetSubKSP(),
PCASMCreateSubdomains2D(), PCASMSetLocalSubdomains(), PCASMGetLocalSubdomains(), PCSetModifySubMatrices()

### Level

advanced

### Location

src/ksp/pc/impls/asm/asm.c
Index of all PC routines
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Index of all manual pages