Cloned SEACAS for EXODUS library with extra build files for internal package management.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

132 lines
3.8 KiB

/*
* Copyright(C) 1999-2020 National Technology & Engineering Solutions
* of Sandia, LLC (NTESS). Under the terms of Contract DE-NA0003525 with
* NTESS, the U.S. Government retains certain rights in this software.
*
* See packages/seacas/LICENSE for details
*/
#include "params.h" // for MAXSETS
#include "smalloc.h" // for sfree, smalloc
#include "structs.h" // for vtx_data
#include <stdio.h> // for printf, NULL
/* Partition vertices into sets in one of several simplistic ways. */
void simple_part(struct vtx_data **graph, /* data structure for graph */
int nvtxs, /* total number of vtxs in graph */
int *sets, /* sets vertices get assigned to */
int nsets, /* number of sets at each division */
int simple_type, /* type of decomposition */
double *goal /* desired set sizes */
)
{
extern int DEBUG_TRACE; /* trace the execution of the code */
double cutoff; /* ending weight for a partition */
double ratio; /* weight/goal */
double best_ratio; /* lowest ratio of weight/goal */
double sum; /* sum of vwgts in a set */
double vwgt; /* vertex weight */
int using_vwgts; /* are vertex weights active? */
int *order; /* random ordering of vertices */
int weight; /* sum of vertex weights in a partition */
int wgts[MAXSETS]; /* weight assigned to given set so far */
int set = 0; /* set vertex is assigned to */
int i, j; /* loop counters */
void randomize(int *array, int n);
using_vwgts = (graph != NULL);
/* Scattered initial decomposition. */
if (simple_type == 1) {
if (DEBUG_TRACE > 0) {
printf("Generating scattered partition, nvtxs = %d\n", nvtxs);
}
for (j = 0; j < nsets; j++) {
wgts[j] = 0;
}
for (i = 1; i <= nvtxs; i++) {
best_ratio = 2;
for (j = 0; j < nsets; j++) {
ratio = wgts[j] / goal[j];
if (ratio < best_ratio) {
best_ratio = ratio;
set = j;
}
}
if (using_vwgts) {
wgts[set] += graph[i]->vwgt;
}
else {
wgts[set]++;
}
sets[i] = set;
}
}
/* Random initial decomposition. */
if (simple_type == 2) {
if (DEBUG_TRACE > 0) {
printf("Generating random partition, nvtxs = %d\n", nvtxs);
}
/* Construct random order in which to step through graph. */
order = smalloc((nvtxs + 1) * sizeof(int));
for (i = 1; i <= nvtxs; i++) {
order[i] = i;
}
randomize(order, nvtxs);
weight = 0;
cutoff = goal[0];
set = 0;
vwgt = 1;
sum = 0;
for (i = 1; i <= nvtxs; i++) {
if (using_vwgts) {
vwgt = graph[order[i]]->vwgt;
}
if (set < nsets - 1 &&
(weight >= cutoff ||
(weight + vwgt >= cutoff && sum + vwgt - goal[set] > vwgt - goal[set + 1]))) {
cutoff += goal[++set];
sum = 0;
}
weight += vwgt;
sum += vwgt;
sets[order[i]] = set;
}
sfree(order);
}
/* Linearly ordered initial decomposition. */
if (simple_type == 3) {
if (DEBUG_TRACE > 0) {
printf("Generating linear partition, nvtxs = %d\n", nvtxs);
}
weight = 0;
cutoff = goal[0];
set = 0;
vwgt = 1;
sum = 0;
for (i = 1; i <= nvtxs; i++) {
if (using_vwgts) {
vwgt = graph[i]->vwgt;
}
if (set < nsets - 1 &&
(weight >= cutoff ||
(weight + vwgt >= cutoff && sum + vwgt - goal[set] > vwgt - goal[set + 1]))) {
cutoff += goal[++set];
sum = 0;
}
weight += vwgt;
sum += vwgt;
sets[i] = set;
}
}
}