void symamd_ord(int n, int A_ptr[], int A_ind[], int P_per[])
{ /* approximate minimum degree ordering (SYMAMD) */
int k, ok;
int stats[COLAMD_STATS];
/* make all indices 0-based */
for (k = 1; k < A_ptr[n+1]; k++) A_ind[k]--;
for (k = 1; k <= n+1; k++) A_ptr[k]--;
/* call the ordering routine */
ok = symamd(n, &A_ind[1], &A_ptr[1], &P_per[1], NULL, stats,
allocate, release);
#if 0
symamd_report(stats);
#endif
xassert(ok);
/* restore 1-based indices */
for (k = 1; k <= n+1; k++) A_ptr[k]++;
for (k = 1; k < A_ptr[n+1]; k++) A_ind[k]++;
/* patch up permutation matrix */
memset(&P_per[n+1], 0, n * sizeof(int));
for (k = 1; k <= n; k++)
{ P_per[k]++;
xassert(1 <= P_per[k] && P_per[k] <= n);
xassert(P_per[n+P_per[k]] == 0);
P_per[n+P_per[k]] = k;
}
return;
}
int __WINAPI getMDO(lprec *lp, MYBOOL *usedpos, int *colorder, int *size, MYBOOL symmetric)
{
int error = FALSE;
int nrows = lp->rows+1, ncols = colorder[0];
int i, j, kk, n;
int *col_end, *row_map = NULL;
int Bnz, Blen, *Brows = NULL;
int stats[COLAMD_STATS];
double knobs[COLAMD_KNOBS];
/* Tally the non-zero counts of the unused columns/rows of the
basis matrix and store corresponding "net" starting positions */
allocINT(lp, &col_end, ncols+1, FALSE);
n = prepareMDO(lp, usedpos, colorder, col_end, NULL);
Bnz = col_end[ncols];
/* Check that we have unused basic columns, otherwise skip analysis */
if(ncols == 0 || Bnz == 0)
goto Transfer;
/* Get net number of rows and fill mapper */
allocINT(lp, &row_map, nrows, FALSE);
nrows = 0;
for(i = 0; i <= lp->rows; i++) {
row_map[i] = i-nrows;
/* Increment eliminated row counter if necessary */
if(!includeMDO(usedpos, i))
nrows++;
}
nrows = lp->rows+1 - nrows;
/* Store row indeces of non-zero values in the basic columns */
Blen = colamd_recommended(Bnz, nrows, ncols);
allocINT(lp, &Brows, Blen, FALSE);
prepareMDO(lp, usedpos, colorder, Brows, row_map);
#ifdef Paranoia
verifyMDO(lp, col_end, Brows, nrows, ncols);
#endif
/* Compute the MDO */
#if 1
colamd_set_defaults(knobs);
knobs [COLAMD_DENSE_ROW] = 0.2+0.2 ; /* default changed for UMFPACK */
knobs [COLAMD_DENSE_COL] = knobs [COLAMD_DENSE_ROW];
if(symmetric && (nrows == ncols)) {
MEMCOPY(colorder, Brows, ncols + 1);
error = !symamd(nrows, colorder, col_end, Brows, knobs, stats, mdo_calloc, mdo_free);
}
else
error = !colamd(nrows, ncols, Blen, Brows, col_end, knobs, stats);
#else
if(symmetric && (nrows == ncols)) {
MEMCOPY(colorder, Brows, ncols + 1);
error = !symamd(nrows, colorder, col_end, Brows, knobs, stats, mdo_calloc, mdo_free);
}
else
error = !colamd(nrows, ncols, Blen, Brows, col_end, (double *) NULL, stats);
#endif
/* Transfer the estimated optimal ordering, adjusting for index offsets */
Transfer:
if(error)
error = stats[COLAMD_STATUS];
else {
MEMCOPY(Brows, colorder, ncols + 1);
for(j = 0; j < ncols; j++) {
kk = col_end[j];
n = Brows[kk+1];
colorder[j+1] = n;
}
}
/* Free temporary vectors */
FREE(col_end);
if(row_map != NULL)
FREE(row_map);
if(Brows != NULL)
FREE(Brows);
if(size != NULL)
*size = ncols;
return( error );
}
