:orphan:
# VecWhichInactive
Creates an index set containing the indices where one of the following holds: a) VecLow(i)  < V(i) < VecHigh(i) b) VecLow(i)  = V(i) and D(i) <= 0 (< 0 when Strong is true) c) VecHigh(i) = V(i) and D(i) >= 0 (> 0 when Strong is true) 
## Synopsis
```
#include "petscvec.h"  
PetscErrorCode VecWhichInactive(Vec VecLow, Vec V, Vec D, Vec VecHigh, PetscBool Strong, IS *S)
```
Collective


## Input Parameters

- ***VecLow -*** lower bound
- ***V -*** Vector to compare
- ***D -*** Direction to compare
- ***VecHigh -*** higher bound
- ***Strong -*** indicator for applying strongly inactive test



## OutputParameter

- ***S -*** The index set containing the indices i where the bound is inactive





## See Also
 `Vec`

## Level
advanced

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


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[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](/manualpages/index.md)  
[Index of all manual pages](/manualpages/singleindex.md)  
