:orphan:
# DMGetBlockSize
Gets the inherent block size associated with a `DM` 
## Synopsis
```
#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMGetBlockSize(DM dm, PetscInt *bs)
```
Not Collective


## Input Parameter

- ***dm -*** the `DM` with block structure



## Output Parameter

- ***bs -*** the block size, 1 implies no exploitable block structure





## Note
This might be the number of degrees of freedom at each grid point for a structured grid.

Complex `DM` that represent multiphysics or staggered grids or mixed-methods do not generally have a single inherent block size, but
rather different locations in the vectors may have a different block size.


## See Also
 [](ch_dmbase), `DM`, `ISCreateBlock()`, `VecSetBlockSize()`, `MatSetBlockSize()`, `DMGetLocalToGlobalMapping()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/interface/dm.c.html#DMGetBlockSize">src/dm/interface/dm.c</A>


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


[Index of all DM routines](index.md)  
[Table of Contents for all manual pages](/manualpages/index.md)  
[Index of all manual pages](/manualpages/singleindex.md)  
