# DMPlexGetFaceGeometry
Retrieve the geometric values for a chunk of faces 
## Synopsis
```
#include "petscdmplex.h"   
PetscErrorCode DMPlexGetFaceGeometry(DM dm, PetscInt fStart, PetscInt fEnd, Vec faceGeometry, Vec cellGeometry, PetscInt *Nface, PetscFVFaceGeom **fgeom, PetscReal **vol)
```

## Input Parameters

- ***dm     -*** The `DM`
- ***fStart -*** The first face to include
- ***fEnd   -*** The first face to exclude
- ***faceGeometry -*** A local vector with face geometry
- ***cellGeometry -*** A local vector with cell geometry



## Output Parameters

- ***Nface -*** The number of faces with field values
- ***fgeom -*** The extract the face centroid and normal
- ***vol   -*** The cell volume





## See Also
 [](chapter_unstructured), `DM`, `DMPLEX`, `DMPlexGetCellFields()`

## Level
developer

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


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


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