# MatSetValuesBlockedLocal
Inserts or adds values into certain locations of a matrix, using a local ordering of the nodes a block at a time. 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatSetValuesBlockedLocal(Mat mat, PetscInt nrow, const PetscInt irow[], PetscInt ncol, const PetscInt icol[], const PetscScalar y[], InsertMode addv)
```
Not Collective


## Input Parameters

- ***x -*** the matrix
- ***nrow, irow -*** number of rows and their local indices
- ***ncol, icol -*** number of columns and their local indices
- ***y -*** a logically two-dimensional array of values
- ***addv -*** either `ADD_VALUES` to add values to any existing entries, or `INSERT_VALUES` to replace existing entries with new values



## Notes
If you create the matrix yourself (that is not with a call to `DMCreateMatrix()`) then you MUST call MatXXXXSetPreallocation() or
`MatSetUp()` before using this routine

If you create the matrix yourself (that is not with a call to `DMCreateMatrix()`) then you MUST call `MatSetBlockSize()` and `MatSetLocalToGlobalMapping()`
before using this routineBefore calling `MatSetValuesLocal()`, the user must first set the

Calls to `MatSetValuesBlockedLocal()` with the `INSERT_VALUES` and `ADD_VALUES`
options cannot be mixed without intervening calls to the assembly
routines.

These values may be cached, so `MatAssemblyBegin()` and `MatAssemblyEnd()`
MUST be called after all calls to `MatSetValuesBlockedLocal()` have been completed.




## Developer Note
This is labeled with C so does not automatically generate Fortran stubs and interfaces
because it requires multiple Fortran interfaces depending on which arguments are scalar or arrays.


## See Also
 `Mat`, `MatSetBlockSize()`, `MatSetLocalToGlobalMapping()`, `MatAssemblyBegin()`, `MatAssemblyEnd()`,
`MatSetValuesLocal()`, `MatSetValuesBlocked()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/interface/matrix.c.html#MatSetValuesBlockedLocal">src/mat/interface/matrix.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex71.c.html">src/ksp/ksp/tutorials/ex71.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex14.c.html">src/ts/tutorials/ex14.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex22f.F90.html">src/ts/tutorials/ex22f.F90.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex22f_mf.F90.html">src/ts/tutorials/ex22f_mf.F90.html</A><BR>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/is/matis.c.html#MatSetValuesBlockedLocal_IS">MatSetValuesBlockedLocal_IS in src/mat/impls/is/matis.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/mat/interface/matrix.c)


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