# PCSetUpOnBlocks
Sets up the preconditioner for each block in the block Jacobi, block Gauss-Seidel, and overlapping Schwarz methods. 
## Synopsis
```
#include "petscksp.h" 
PetscErrorCode PCSetUpOnBlocks(PC pc)
```
Collective


## Input Parameter

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





## Note
For nested preconditioners such as `PCBJACOBI` `PCSetUp()` is not called on each sub-`KSP` when `PCSetUp()` is
called on the outer `PC`, this routine ensures it is called.


## See Also
 `PC`, `PCSetUp()`, `PCCreate()`, `PCApply()`, `PCDestroy()`, `PCSetUp()`

## Level
developer

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

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/asm/asm.c.html#PCSetUpOnBlocks_ASM">PCSetUpOnBlocks_ASM in src/ksp/pc/impls/asm/asm.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/gasm/gasm.c.html#PCSetUpOnBlocks_GASM">PCSetUpOnBlocks_GASM in src/ksp/pc/impls/gasm/gasm.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/patch/pcpatch.c.html#PCSetUpOnBlocks_PATCH">PCSetUpOnBlocks_PATCH in src/ksp/pc/impls/patch/pcpatch.c</A><BR>


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[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](/docs/manualpages/index.md)  
[Index of all manual pages](/docs/manualpages/singleindex.md)  
