:orphan:
# DMProjectFunctionLabel
This projects the given function into the function space provided by the `DM`, putting the coefficients in a global vector, setting values only for points in the given label. 
## Synopsis
```
#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMProjectFunctionLabel(DM dm, PetscReal time, DMLabel label, PetscInt numIds, const PetscInt ids[], PetscInt Nc, const PetscInt comps[], PetscErrorCode (**funcs)(PetscInt, PetscReal, const PetscReal[], PetscInt, PetscScalar *, void *), void **ctxs, InsertMode mode, Vec X)
```
Collective


## Input Parameters

- ***dm      -*** The `DM`
- ***time    -*** The time
- ***label   -*** The `DMLabel` selecting the portion of the mesh for projection
- ***funcs   -*** The coordinate functions to evaluate, one per field
- ***ctxs    -*** Optional array of contexts to pass to each coordinate function.  ctxs may be null.
- ***mode    -*** The insertion mode for values



## Output Parameter

- ***X -*** vector



## Calling sequence of `funcs`
```none
PetscErrorCode funcs(PetscInt dim, PetscReal time, const PetscReal x[], PetscInt Nc, PetscScalar u[], void *ctx);
```

- ***dim -*** The spatial dimension
- ***x   -*** The coordinates
- ***Nc  -*** The number of components
- ***u   -*** The output field values
- ***ctx -*** optional user-defined function context





## Developer Notes
This API is specific to only particular usage of `DM`

The notes need to provide some information about what has to be provided to the `DM` to be able to perform the computation.


## See Also
 [](ch_dmbase), `DM`, `DMProjectFunction()`, `DMProjectFunctionLocal()`, `DMProjectFunctionLabelLocal()`, `DMComputeL2Diff()`

## Level
developer

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


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