# PetscSectionCreateSubdomainSection
Create a new, smaller section with support on a subdomain of the mesh 
## Synopsis
```
#include "petscsection.h"   
PetscErrorCode PetscSectionCreateSubdomainSection(PetscSection s, IS subpointMap, PetscSection *subs)
```
Collective on s


## Input Parameters

- ***s           -*** the `PetscSection`
- ***subpointMap -*** a sorted list of points in the original mesh which are in the subdomain



## Output Parameter

- ***subs -*** the subsection





## Note
The point numbers remain the same, but the section offsets now refer to a new, smaller vector.


## Developer Notes
It is unclear what the difference with `PetscSectionCreateSubmeshSection()` is.

The use of the term Subdomain is unneeded and confusing


## See Also
 [PetscSection](sec_petscsection), `PetscSection`, `PetscSectionCreateSubmeshSection()`, `PetscSectionCreateSubsection()`, `DMPlexGetSubpointMap()`, `PetscSectionCreate()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/is/section/interface/section.c.html#PetscSectionCreateSubdomainSection">src/vec/is/section/interface/section.c</A>


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