:orphan:
# PCMatApply
Applies the preconditioner to multiple vectors stored as a `MATDENSE`. Like `PCApply()`, Y and X must be different matrices.
## Synopsis
```
#include "petscksp.h"
PetscErrorCode PCMatApply(PC pc, Mat X, Mat Y)
```
Collective
## Input Parameters
- ***pc -*** the preconditioner context
- ***X -*** block of input vectors
## Output Parameter
- ***Y -*** block of output vectors
## See Also
`PC`, `PCApply()`, `KSPMatSolve()`
## Level
developer
## Location
src/ksp/pc/interface/precon.c
## Examples
src/ksp/ksp/tutorials/ex79.c
## Implementations
PCMatApply_ASM in src/ksp/pc/impls/asm/asm.c
PCMatApply_Cholesky in src/ksp/pc/impls/factor/cholesky/cholesky.c
PCMatApply_ICC in src/ksp/pc/impls/factor/icc/icc.c
PCMatApply_ILU in src/ksp/pc/impls/factor/ilu/ilu.c
PCMatApply_LU in src/ksp/pc/impls/factor/lu/lu.c
PCMatApply_QR in src/ksp/pc/impls/factor/qr/qr.c
PCMatApply_GASM in src/ksp/pc/impls/gasm/gasm.c
PCMatApply_HPDDM in src/ksp/pc/impls/hpddm/pchpddm.cxx
PCMatApply_HPDDMShell in src/ksp/pc/impls/hpddm/pchpddm.cxx
PCMatApply_KSP in src/ksp/pc/impls/ksp/pcksp.c
PCMatApply_Mat in src/ksp/pc/impls/mat/pcmat.c
PCMatApply_MG in src/ksp/pc/impls/mg/mg.c
PCMatApply_None in src/ksp/pc/impls/none/none.c
PCMatApply_Shell in src/ksp/pc/impls/shell/shellpc.c
PCMatApply_SPAI in src/ksp/pc/impls/spai/ispai.c
PCMatApply_SVD in src/ksp/pc/impls/svd/svd.c
---
[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/ksp/pc/interface/precon.c)
[Index of all PC routines](index.md)
[Table of Contents for all manual pages](/manualpages/index.md)
[Index of all manual pages](/manualpages/singleindex.md)