1 #if !defined(PETSCSFTYPES_H)
2 #define PETSCSFTYPES_H
3 
4 /*S
5    PetscSF - PETSc object for setting up and managing the communication of certain entries of arrays and Vecs between MPI processes.
6 
7    Level: intermediate
8 
9        PetscSF uses the concept of star forests to indicate and determine the communication patterns concisely and efficiently.
10   A star  https://en.wikipedia.org/wiki/Star_(graph_theory) forest is simply a collection of trees of height 1. The leave nodes represent
11   "ghost locations" for the root nodes.
12 
13 .seealso: PetscSFCreate(), VecScatter, VecScatterCreate()
14 S*/
15 typedef struct _p_PetscSF* PetscSF;
16 
17 /*S
18    PetscSFNode - specifier of owner and index
19 
20    Level: beginner
21 
22   Sample Usage:
23 $      PetscSFNode    *remote;
24 $    ierr = PetscMalloc1(nleaves,&remote);CHKERRQ(ierr);
25 $    for (i=0; i<size; i++) {
26 $      remote[i].rank = i;
27 $      remote[i].index = rank;
28 $    }
29 
30   Sample Fortran Usage:
31 $     type(PetscSFNode) remote(6)
32 $      remote(1)%rank  = modulo(rank+size-1,size)
33 $      remote(1)%index = 1 * stride
34 
35 .seealso: PetscSFSetGraph()
36 S*/
37 typedef struct {
38   PetscInt rank;                /* Rank of owner */
39   PetscInt index;               /* Index of node on rank */
40 } PetscSFNode;
41 
42 #endif
43