/*
* CXSPARSE: a Concise Sparse Matrix package - Extended.
* Copyright (c) 2006-2009, Timothy A. Davis.
* http://www.cise.ufl.edu/research/sparse/CXSparse
*
* CXSparse is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* CXSparse is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this Module; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "cs.h"
/* remove duplicate entries from A */
CS_INT cs_dupl (cs *A)
{
CS_INT i, j, p, q, nz = 0, n, m, *Ap, *Ai, *w ;
CS_ENTRY *Ax ;
if (!CS_CSC (A)) return (0) ; /* check inputs */
m = A->m ; n = A->n ; Ap = A->p ; Ai = A->i ; Ax = A->x ;
w = cs_malloc (m, sizeof (CS_INT)) ; /* get workspace */
if (!w) return (0) ; /* out of memory */
for (i = 0 ; i < m ; i++) w [i] = -1 ; /* row i not yet seen */
for (j = 0 ; j < n ; j++)
{
q = nz ; /* column j will start at q */
for (p = Ap [j] ; p < Ap [j+1] ; p++)
{
i = Ai [p] ; /* A(i,j) is nonzero */
if (w [i] >= q)
{
Ax [w [i]] += Ax [p] ; /* A(i,j) is a duplicate */
}
else
{
w [i] = nz ; /* record where row i occurs */
Ai [nz] = i ; /* keep A(i,j) */
Ax [nz++] = Ax [p] ;
}
}
Ap [j] = q ; /* record start of column j */
}
Ap [n] = nz ; /* finalize A */
cs_free (w) ; /* free workspace */
return (cs_sprealloc (A, 0)) ; /* remove extra space from A */
}