:orphan:
# PetscSFComputeMultiRootOriginalNumbering
Returns original numbering of multi-roots (roots of multi-`PetscSF` returned by `PetscSFGetMultiSF()`). Each multi-root is assigned index of the corresponding original root.
## Synopsis
```
#include "petscsf.h"
PetscErrorCode PetscSFComputeMultiRootOriginalNumbering(PetscSF sf, const PetscInt degree[], PetscInt *nMultiRoots, PetscInt *multiRootsOrigNumbering[])
```
Collective
## Input Parameters
- ***sf -*** star forest
- ***degree -*** degree of each root vertex, computed with `PetscSFComputeDegreeBegin()`/`PetscSFComputeDegreeEnd()`
## Output Parameters
- ***nMultiRoots -*** (optional) number of multi-roots (roots of multi-`PetscSF`)
- ***multiRootsOrigNumbering -*** original indices of multi-roots; length of this array is `nMultiRoots`
## Note
The returned array `multiRootsOrigNumbering` is newly allocated and should be destroyed with `PetscFree()` when no longer needed.
## See Also
`PetscSF`, `PetscSFComputeDegreeBegin()`, `PetscSFComputeDegreeEnd()`, `PetscSFGetMultiSF()`
## Level
developer
## Location
src/vec/is/sf/interface/sf.c
## Examples
src/vec/is/sf/tutorials/ex1.c
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[Index of all PetscSF routines](index.md)
[Table of Contents for all manual pages](/manualpages/index.md)
[Index of all manual pages](/manualpages/singleindex.md)