**petsc-dev 2014-04-14**

# DMPlexStratify

The Sieve DAG for most topologies is a graded poset (http://en.wikipedia.org/wiki/Graded_poset), and can be illustrated by Hasse Diagram (a http://en.wikipedia.org/wiki/Hasse_diagram). The strata group all points of the same grade, and this function calculates the strata. This grade can be seen as the height (or depth) of the point in the DAG.
### Synopsis

#include "petscdmplex.h"
PetscErrorCode DMPlexStratify(DM dm)

Not collective

### Input Parameter

**mesh ** -The DMPlex

### Output Parameter

### Notes

The normal association for the point grade is element dimension (or co-dimension). For instance, all vertices would
have depth 0, and all edges depth 1. Likewise, all cells heights would have height 0, and all faces height 1.
This should be called after all calls to DMPlexSymmetrize()

### See Also

DMPlexCreate(), DMPlexSymmetrize()

**Level:**beginner

Location:src/dm/impls/plex/plex.c

Index of all DM routines

Table of Contents for all manual pages

Index of all manual pages

### Examples

src/ts/examples/tutorials/ex11.c.html