Actual source code: qmdupd.c
2: /* qmdupd.f -- translated by f2c (version 19931217).*/
4: #include <petscsys.h>
5: #include <petsc/private/matorderimpl.h>
7: /******************************************************************/
8: /*********** QMDUPD ..... QUOT MIN DEG UPDATE ************/
9: /******************************************************************/
10: /******************************************************************/
12: /* PURPOSE - THIS ROUTINE PERFORMS DEGREE UPDATE FOR A SET*/
13: /* OF NODES IN THE MINIMUM DEGREE ALGORITHM.*/
15: /* INPUT PARAMETERS -*/
16: /* (XADJ, ADJNCY) - THE ADJACENCY STRUCTURE.*/
17: /* (NLIST, LIST) - THE LIST OF NODES WHOSE DEGREE HAS TO*/
18: /* BE UPDATED.*/
20: /* UPDATED PARAMETERS -*/
21: /* DEG - THE DEGREE VECTOR.*/
22: /* QSIZE - SIZE OF INDISTINGUISHABLE SUPERNODES.*/
23: /* QLINK - LINKED LIST FOR INDISTINGUISHABLE NODES.*/
24: /* MARKER - USED TO MARK THOSE NODES IN REACH/NBRHD SETS.*/
26: /* WORKING PARAMETERS -*/
27: /* RCHSET - THE REACHABLE SET.*/
28: /* NBRHD - THE NEIGHBORHOOD SET.*/
30: /* PROGRAM SUBROUTINES -*/
31: /* QMDMRG.*/
32: /******************************************************************/
33: PetscErrorCode SPARSEPACKqmdupd(const PetscInt *xadj, const PetscInt *adjncy, const PetscInt *nlist, const PetscInt *list, PetscInt *deg, PetscInt *qsize, PetscInt *qlink, PetscInt *marker, PetscInt *rchset, PetscInt *nbrhd)
34: {
35: /* System generated locals */
36: PetscInt i__1, i__2;
38: /* Local variables */
39: PetscInt inhd, irch, node, mark, j, inode, nabor, jstop, jstrt, il;
40: PetscInt nhdsze, rchsze, deg0, deg1;
42: /* FIND ALL ELIMINATED SUPERNODES THAT ARE ADJACENT*/
43: /* TO SOME NODES IN THE GIVEN LIST. PUT THEM INTO.*/
44: /* (NHDSZE, NBRHD). DEG0 CONTAINS THE NUMBER OF*/
45: /* NODES IN THE LIST.*/
47: /* Parameter adjustments */
48: --nbrhd;
49: --rchset;
50: --marker;
51: --qlink;
52: --qsize;
53: --deg;
54: --list;
55: --adjncy;
56: --xadj;
58: if (*nlist <= 0) return 0;
59: deg0 = 0;
60: nhdsze = 0;
61: i__1 = *nlist;
62: for (il = 1; il <= i__1; ++il) {
63: node = list[il];
64: deg0 += qsize[node];
65: jstrt = xadj[node];
66: jstop = xadj[node + 1] - 1;
67: i__2 = jstop;
68: for (j = jstrt; j <= i__2; ++j) {
69: nabor = adjncy[j];
70: if (marker[nabor] != 0 || deg[nabor] >= 0) goto L100;
71: marker[nabor] = -1;
72: ++nhdsze;
73: nbrhd[nhdsze] = nabor;
74: L100:;
75: }
76: }
77: /* MERGE INDISTINGUISHABLE NODES IN THE LIST BY*/
78: /* CALLING THE SUBROUTINE QMDMRG.*/
79: if (nhdsze > 0) SPARSEPACKqmdmrg(&xadj[1], &adjncy[1], °[1], &qsize[1], &qlink[1], &marker[1], °0, &nhdsze, &nbrhd[1], &rchset[1], &nbrhd[nhdsze + 1]);
80: /* FIND THE NEW DEGREES OF THE NODES THAT HAVE NOT BEEN*/
81: /* MERGED.*/
82: i__1 = *nlist;
83: for (il = 1; il <= i__1; ++il) {
84: node = list[il];
85: mark = marker[node];
86: if (mark > 1 || mark < 0) goto L600;
87: marker[node] = 2;
88: SPARSEPACKqmdrch(&node, &xadj[1], &adjncy[1], °[1], &marker[1], &rchsze, &rchset[1], &nhdsze, &nbrhd[1]);
89: deg1 = deg0;
90: if (rchsze <= 0) goto L400;
91: i__2 = rchsze;
92: for (irch = 1; irch <= i__2; ++irch) {
93: inode = rchset[irch];
94: deg1 += qsize[inode];
95: marker[inode] = 0;
96: }
97: L400:
98: deg[node] = deg1 - 1;
99: if (nhdsze <= 0) goto L600;
100: i__2 = nhdsze;
101: for (inhd = 1; inhd <= i__2; ++inhd) {
102: inode = nbrhd[inhd];
103: marker[inode] = 0;
104: }
105: L600:;
106: }
107: return 0;
108: }