:orphan:
# PetscDSSelectEquations
Copy pointwise function pointers to the new problem with different field layout 
## Synopsis
```
#include "petscds.h" 
PetscErrorCode PetscDSSelectEquations(PetscDS prob, PetscInt numFields, const PetscInt fields[], PetscDS newprob)
```
Not Collective


## Input Parameters

- ***prob -*** The `PetscDS` object
- ***numFields -*** Number of new fields
- ***fields -*** Old field number for each new field



## Output Parameter

- ***newprob -*** The `PetscDS` copy





## See Also
 `PetscDS`, `PetscDSSelectDiscretizations()`, `PetscDSCopyBoundary()`, `PetscDSSetResidual()`, `PetscDSSetJacobian()`, `PetscDSSetRiemannSolver()`, `PetscDSSetBdResidual()`, `PetscDSSetBdJacobian()`, `PetscDSCreate()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/dt/interface/dtds.c.html#PetscDSSelectEquations">src/dm/dt/interface/dtds.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/dm/dt/interface/dtds.c)


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