:orphan:
# PCSetFromOptions
Sets PC options from the options database. This routine must be called before PCSetUp() if the user is to be allowed to set the preconditioner method. 
## Synopsis
```
#include "petscpc.h" 
PetscErrorCode PCSetFromOptions(PC pc)
```
Collective


## Input Parameter

- ***pc -*** the preconditioner context



## Options Database Key

- ***-pc_use_amat true,false -*** see PCSetUseAmat()





## See Also
 `PCSetUseAmat()`


## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/interface/pcset.c.html#PCSetFromOptions">src/ksp/pc/interface/pcset.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex76.c.html">src/ksp/ksp/tutorials/ex76.c</A><BR>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/amgx/amgx.cxx.html#PCSetFromOptions_AMGX">PCSetFromOptions_AMGX in src/ksp/pc/impls/amgx/amgx.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/asm/asm.c.html#PCSetFromOptions_ASM">PCSetFromOptions_ASM in src/ksp/pc/impls/asm/asm.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/bddc/bddc.c.html#PCSetFromOptions_BDDC">PCSetFromOptions_BDDC in src/ksp/pc/impls/bddc/bddc.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/bjacobi/bjacobi.c.html#PCSetFromOptions_BJacobi">PCSetFromOptions_BJacobi in src/ksp/pc/impls/bjacobi/bjacobi.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/bjacobi/bjkokkos/bjkokkos.kokkos.cxx.html#PCSetFromOptions_BJKOKKOS">PCSetFromOptions_BJKOKKOS in src/ksp/pc/impls/bjacobi/bjkokkos/bjkokkos.kokkos.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/chowiluviennacl/chowiluviennacl.cxx.html#PCSetFromOptions_CHOWILUVIENNACL">PCSetFromOptions_CHOWILUVIENNACL in src/ksp/pc/impls/chowiluviennacl/chowiluviennacl.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/composite/composite.c.html#PCSetFromOptions_Composite">PCSetFromOptions_Composite in src/ksp/pc/impls/composite/composite.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/cp/cp.c.html#PCSetFromOptions_CP">PCSetFromOptions_CP in src/ksp/pc/impls/cp/cp.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/deflation/deflation.c.html#PCSetFromOptions_Deflation">PCSetFromOptions_Deflation in src/ksp/pc/impls/deflation/deflation.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/eisens/eisen.c.html#PCSetFromOptions_Eisenstat">PCSetFromOptions_Eisenstat in src/ksp/pc/impls/eisens/eisen.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/factor/cholesky/cholesky.c.html#PCSetFromOptions_Cholesky">PCSetFromOptions_Cholesky in src/ksp/pc/impls/factor/cholesky/cholesky.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/factor/factimpl.c.html#PCSetFromOptions_Factor">PCSetFromOptions_Factor in src/ksp/pc/impls/factor/factimpl.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/factor/icc/icc.c.html#PCSetFromOptions_ICC">PCSetFromOptions_ICC in src/ksp/pc/impls/factor/icc/icc.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/factor/ilu/ilu.c.html#PCSetFromOptions_ILU">PCSetFromOptions_ILU in src/ksp/pc/impls/factor/ilu/ilu.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/factor/lu/lu.c.html#PCSetFromOptions_LU">PCSetFromOptions_LU in src/ksp/pc/impls/factor/lu/lu.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/fieldsplit/fieldsplit.c.html#PCSetFromOptions_FieldSplit">PCSetFromOptions_FieldSplit in src/ksp/pc/impls/fieldsplit/fieldsplit.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/galerkin/galerkin.c.html#PCSetFromOptions_Galerkin">PCSetFromOptions_Galerkin in src/ksp/pc/impls/galerkin/galerkin.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/gamg/gamg.c.html#PCSetFromOptions_GAMG">PCSetFromOptions_GAMG in src/ksp/pc/impls/gamg/gamg.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/gamg/geo.c.html#PCSetFromOptions_GEO">PCSetFromOptions_GEO in src/ksp/pc/impls/gamg/geo.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/gasm/gasm.c.html#PCSetFromOptions_GASM">PCSetFromOptions_GASM in src/ksp/pc/impls/gasm/gasm.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/h2opus/pch2opus.c.html#PCSetFromOptions_H2OPUS">PCSetFromOptions_H2OPUS in src/ksp/pc/impls/h2opus/pch2opus.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/hmg/hmg.c.html#PCSetFromOptions_HMG">PCSetFromOptions_HMG in src/ksp/pc/impls/hmg/hmg.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/hpddm/pchpddm.cxx.html#PCSetFromOptions_HPDDM">PCSetFromOptions_HPDDM in src/ksp/pc/impls/hpddm/pchpddm.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/hypre/hypre.c.html#PCSetFromOptions_HYPRE">PCSetFromOptions_HYPRE in src/ksp/pc/impls/hypre/hypre.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/hypre/hypre.c.html#PCSetFromOptions_PFMG">PCSetFromOptions_PFMG in src/ksp/pc/impls/hypre/hypre.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/hypre/hypre.c.html#PCSetFromOptions_SysPFMG">PCSetFromOptions_SysPFMG in src/ksp/pc/impls/hypre/hypre.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/hypre/hypre.c.html#PCSetFromOptions_SMG">PCSetFromOptions_SMG in src/ksp/pc/impls/hypre/hypre.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/jacobi/jacobi.c.html#PCSetFromOptions_Jacobi">PCSetFromOptions_Jacobi in src/ksp/pc/impls/jacobi/jacobi.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/kaczmarz/kaczmarz.c.html#PCSetFromOptions_Kaczmarz">PCSetFromOptions_Kaczmarz in src/ksp/pc/impls/kaczmarz/kaczmarz.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/ksp/pcksp.c.html#PCSetFromOptions_KSP">PCSetFromOptions_KSP in src/ksp/pc/impls/ksp/pcksp.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/lmvm/lmvmpc.c.html#PCSetFromOptions_LMVM">PCSetFromOptions_LMVM in src/ksp/pc/impls/lmvm/lmvmpc.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/lsc/lsc.c.html#PCSetFromOptions_LSC">PCSetFromOptions_LSC in src/ksp/pc/impls/lsc/lsc.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/mg/mg.c.html#PCSetFromOptions_MG">PCSetFromOptions_MG in src/ksp/pc/impls/mg/mg.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/ml/ml.c.html#PCSetFromOptions_ML">PCSetFromOptions_ML in src/ksp/pc/impls/ml/ml.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/mpi/pcmpi.c.html#PCSetFromOptions_MPI">PCSetFromOptions_MPI in src/ksp/pc/impls/mpi/pcmpi.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/parms/parms.c.html#PCSetFromOptions_PARMS">PCSetFromOptions_PARMS in src/ksp/pc/impls/parms/parms.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/patch/pcpatch.c.html#PCSetFromOptions_PATCH">PCSetFromOptions_PATCH in src/ksp/pc/impls/patch/pcpatch.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/redistribute/redistribute.c.html#PCSetFromOptions_Redistribute">PCSetFromOptions_Redistribute in src/ksp/pc/impls/redistribute/redistribute.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/redundant/redundant.c.html#PCSetFromOptions_Redundant">PCSetFromOptions_Redundant in src/ksp/pc/impls/redundant/redundant.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/rowscalingviennacl/rowscalingviennacl.cxx.html#PCSetFromOptions_ROWSCALINGVIENNACL">PCSetFromOptions_ROWSCALINGVIENNACL in src/ksp/pc/impls/rowscalingviennacl/rowscalingviennacl.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/saviennacl/saviennacl.cxx.html#PCSetFromOptions_SAVIENNACL">PCSetFromOptions_SAVIENNACL in src/ksp/pc/impls/saviennacl/saviennacl.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/sor/sor.c.html#PCSetFromOptions_SOR">PCSetFromOptions_SOR in src/ksp/pc/impls/sor/sor.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/spai/ispai.c.html#PCSetFromOptions_SPAI">PCSetFromOptions_SPAI in src/ksp/pc/impls/spai/ispai.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/svd/svd.c.html#PCSetFromOptions_SVD">PCSetFromOptions_SVD in src/ksp/pc/impls/svd/svd.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/telescope/telescope.c.html#PCSetFromOptions_Telescope">PCSetFromOptions_Telescope in src/ksp/pc/impls/telescope/telescope.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/tfs/tfs.c.html#PCSetFromOptions_TFS">PCSetFromOptions_TFS in src/ksp/pc/impls/tfs/tfs.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/wb/wb.c.html#PCSetFromOptions_Exotic">PCSetFromOptions_Exotic in src/ksp/pc/impls/wb/wb.c</A><BR>


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