:orphan:
# DMPlexVecGetClosure
Get an array of the values on the closure of 'point' 
## Synopsis
```
#include "petscdmplex.h"   
PetscErrorCode DMPlexVecGetClosure(DM dm, PetscSection section, Vec v, PetscInt point, PetscInt *csize, PetscScalar *values[])
```
Not collective


## Input Parameters

- ***dm -*** The `DM`
- ***section -*** The section describing the layout in `v`, or `NULL` to use the default section
- ***v -*** The local vector
- ***point -*** The point in the `DM`



## Input/Output Parameters

- ***csize  -*** The size of the input values array, or `NULL`; on output the number of values in the closure
- ***values -*** An array to use for the values, or `NULL` to have it allocated automatically;
if the user provided `NULL`, it is a borrowed array and should not be freed





## Notes
`DMPlexVecGetClosure()`/`DMPlexVecRestoreClosure()` only allocates the values array if it set to `NULL` in the
calling function. This is because `DMPlexVecGetClosure()` is typically called in the inner loop of a `Vec` or `Mat`
assembly function, and a user may already have allocated storage for this operation.

A typical use could be
```none
   values = NULL;
   PetscCall(DMPlexVecGetClosure(dm, NULL, v, p, &clSize, &values));
   for (cl = 0; cl < clSize; ++cl) {
     <Compute on closure>
   }
   PetscCall(DMPlexVecRestoreClosure(dm, NULL, v, p, &clSize, &values));
```

or
```none
   PetscMalloc1(clMaxSize, &values);
   for (p = pStart; p < pEnd; ++p) {
     clSize = clMaxSize;
     PetscCall(DMPlexVecGetClosure(dm, NULL, v, p, &clSize, &values));
     for (cl = 0; cl < clSize; ++cl) {
       <Compute on closure>
     }
   }
   PetscFree(values);
```



## Fortran Note
The `csize` argument is not present in the Fortran binding since it is internal to the array.


## See Also
 [](ch_unstructured), `DM`, `DMPLEX`, `DMPlexVecRestoreClosure()`, `DMPlexVecSetClosure()`, `DMPlexMatSetClosure()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/plex/plex.c.html#DMPlexVecGetClosure">src/dm/impls/plex/plex.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/plex/tutorials/ex11.c.html">src/dm/impls/plex/tutorials/ex11.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/plex/tutorials/ex6.c.html">src/dm/impls/plex/tutorials/ex6.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex56.c.html">src/snes/tutorials/ex56.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex77.c.html">src/snes/tutorials/ex77.c</A><BR>


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


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