umf_fsize.c 2.19 KB
/* ========================================================================== */
/* === UMF_fsize ============================================================ */
/* ========================================================================== */
/* -------------------------------------------------------------------------- */
/* UMFPACK Copyright (c) Timothy A. Davis, CISE, */
/* Univ. of Florida. All Rights Reserved. See ../Doc/License for License. */
/* web: http://www.cise.ufl.edu/research/sparse/umfpack */
/* -------------------------------------------------------------------------- */
/* Determine the largest frontal matrix size for each subtree. Called by
* UMF_colamd and UMF_analyze. Only required to sort the children of each
* node prior to AMD_postorder. */
#include "umf_internal.h"
GLOBAL void UMF_fsize
(
Int nn,
Int Fsize [ ],
Int Fnrows [ ],
Int Fncols [ ],
Int Parent [ ],
Int Npiv [ ]
)
{
Int j, parent, frsize, r, c ;
for (j = 0 ; j < nn ; j++)
{
Fsize [j] = EMPTY ;
}
/* ---------------------------------------------------------------------- */
/* find max front size for tree rooted at node j, for each front j */
/* ---------------------------------------------------------------------- */
DEBUG1 (("\n\n========================================FRONTS:\n")) ;
for (j = 0 ; j < nn ; j++)
{
if (Npiv [j] > 0)
{
/* this is a frontal matrix */
parent = Parent [j] ;
r = Fnrows [j] ;
c = Fncols [j] ;
frsize = r * c ;
/* avoid integer overflow */
if (INT_OVERFLOW (((double) r) * ((double) c)))
{
/* :: frsize int overflow :: */
frsize = Int_MAX ;
}
DEBUG1 ((""ID" : npiv "ID" size "ID" parent "ID" ",
j, Npiv [j], frsize, parent)) ;
Fsize [j] = MAX (Fsize [j], frsize) ;
DEBUG1 (("Fsize [j = "ID"] = "ID"\n", j, Fsize [j])) ;
if (parent != EMPTY)
{
/* find the maximum frontsize of self and children */
ASSERT (Npiv [parent] > 0) ;
ASSERT (parent > j) ;
Fsize [parent] = MAX (Fsize [parent], Fsize [j]) ;
DEBUG1 (("Fsize [parent = "ID"] = "ID"\n",
parent, Fsize [parent]));
}
}
}
}