:orphan:
# MPI_Comm
the basic object used by MPI to determine which processes are involved in a communication 


## Note
This manual page is a place-holder because MPICH does not have a manual page for `MPI_Comm`


## See Also
 `PETSC_COMM_WORLD`, `PETSC_COMM_SELF`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscsys.h.html#MPI_Comm">include/petscsys.h</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex65.c.html">src/ksp/ksp/tutorials/ex65.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex74.c.html">src/ksp/ksp/tutorials/ex74.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex15.c.html">src/snes/tutorials/ex15.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/classes/random/tutorials/ex2.c.html">src/sys/classes/random/tutorials/ex2.c</A><BR>


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