:orphan:
# PCSHELL
Creates a new preconditioner class for use with a users own private data storage format and preconditioner application code 


## Usage
```none
       extern PetscErrorCode apply(PC,Vec,Vec);
       extern PetscErrorCode applyba(PC,PCSide,Vec,Vec,Vec);
       extern PetscErrorCode applytranspose(PC,Vec,Vec);
       extern PetscErrorCode setup(PC);
       extern PetscErrorCode destroy(PC);

       PCCreate(comm,&pc);
       PCSetType(pc,PCSHELL);
       PCShellSetContext(pc,ctx)
       PCShellSetApply(pc,apply);
       PCShellSetApplyBA(pc,applyba);               (optional)
       PCShellSetApplyTranspose(pc,applytranspose); (optional)
       PCShellSetSetUp(pc,setup);                   (optional)
       PCShellSetDestroy(pc,destroy);               (optional)
```



## See Also
 `PCCreate()`, `PCSetType()`, `PCType`, `PC`,
`MATSHELL`, `PCShellSetSetUp()`, `PCShellSetApply()`, `PCShellSetView()`, `PCShellSetDestroy()`, `PCShellSetPostSolve()`,
`PCShellSetApplyTranspose()`, `PCShellSetName()`, `PCShellSetApplyRichardson()`, `PCShellSetPreSolve()`, `PCShellSetView()`,
`PCShellGetName()`, `PCShellSetContext()`, `PCShellGetContext()`, `PCShellSetApplyBA()`, `MATSHELL`, `PCShellSetMatApply()`,

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/shell/shellpc.c.html#PCSHELL">src/ksp/pc/impls/shell/shellpc.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex15.c.html">src/ksp/ksp/tutorials/ex15.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex15f.F90.html">src/ksp/ksp/tutorials/ex15f.F90</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex60.c.html">src/ksp/ksp/tutorials/ex60.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex3.c.html">src/snes/tutorials/ex3.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/tao/pde_constrained/tutorials/hyperbolic.c.html">src/tao/pde_constrained/tutorials/hyperbolic.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/tao/pde_constrained/tutorials/parabolic.c.html">src/tao/pde_constrained/tutorials/parabolic.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/ksp/pc/impls/shell/shellpc.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)