# DMGetOutputDM
Retrieve the `DM` associated with the layout for output 
## Synopsis
```
#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMGetOutputDM(DM dm, DM *odm)
```
Collective on dm


## Input Parameter

- ***dm -*** The original `DM`



## Output Parameter

- ***odm -*** The `DM` which provides the layout for output





## Note
In some situations the vector obtained with `DMCreateGlobalVector()` excludes points for degrees of freedom that are associated with fixed (Dirichelet) boundary
conditions since the algebraic solver does not solve for those variables. The output `DM` includes these excluded points and its global vector contains the
locations for those dof so that they can be output to a file or other viewer along with the unconstrained dof.


## See Also
 `VecView()`, `DMGetGlobalSection()`, `DMCreateGlobalVector()`, `PetscSectionHasConstraints()`, `DMSetGlobalSection()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/interface/dm.c.html#DMGetOutputDM">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](/docs/manualpages/index.md)  
[Index of all manual pages](/docs/manualpages/singleindex.md)  
