# PCApplyTransposeExists
Test whether the preconditioner has a transpose apply operation 
## Synopsis
```
#include "petscksp.h" 
PetscErrorCode PCApplyTransposeExists(PC pc, PetscBool *flg)
```
Collective


## Input Parameter

- ***pc -*** the preconditioner context



## Output Parameter

- ***flg -*** `PETSC_TRUE` if a transpose operation is defined





## See Also
 `PC`, `PCApplyTranspose()`

## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/interface/precon.c.html#PCApplyTransposeExists">src/ksp/pc/interface/precon.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/ksp/pc/interface/precon.c)


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