# DMPlexSetTree
set the tree that describes the hierarchy of non-conforming mesh points.  This routine also creates the point-to-point constraints determined by the tree: a point is constained to the points in the closure of its tree root. 
## Synopsis
```
#include "petscdmplex.h"   
PetscErrorCode DMPlexSetTree(DM dm, PetscSection parentSection, PetscInt parents[], PetscInt childIDs[])
```
Collective on dm


## Input Parameters

- ***dm -*** the `DMPLEX` object
- ***parentSection -*** a section describing the tree: a point has a parent if it has 1 dof in the section; the section
offset indexes the parent and childID list; the reference count of parentSection is incremented
- ***parents -*** a list of the point parents; copied, can be destroyed
- ***childIDs -*** identifies the relationship of the child point to the parent point; if there is a reference tree, then
the child corresponds to the point in the reference tree with index childIDs; copied, can be destroyed





## See Also
 [](chapter_unstructured), `DM`, `DMPLEX`, `DMPlexGetTree()`, `DMPlexSetReferenceTree()`, `DMPlexSetAnchors()`, `DMPlexGetTreeParent()`, `DMPlexGetTreeChildren()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/plex/plextree.c.html#DMPlexSetTree">src/dm/impls/plex/plextree.c</A>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/plex/plextree.c.html#DMPlexSetTree_Internal">DMPlexSetTree_Internal in src/dm/impls/plex/plextree.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/dm/impls/plex/plextree.c)


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