# ISComplementVec
Creates the complement of the index set relative to a layout defined by a Vec 
## Synopsis
```
#include "petscvec.h"  
PetscErrorCode ISComplementVec(IS S, Vec V, IS *T)
```
Collective on IS


## Input Parameters

- ***S -*** a PETSc IS
- ***V -*** the reference vector space



## Output Parameter

- ***T -*** the complement of S





## See Also
 `ISCreateGeneral()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/utils/projection.c.html#ISComplementVec">src/vec/vec/utils/projection.c</A>


---
[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/vec/vec/utils/projection.c)


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