1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
|
#include "cs.h"
/* drop entries for which fkeep(A(i,j)) is false; return nz if OK, else -1 */
int cs_fkeep (cs *A, int (*fkeep) (int, int, double, void *), void *other)
{
int j, p, nz = 0, n, *Ap, *Ai ;
double *Ax ;
if (!CS_CSC (A) || !fkeep) return (-1) ; /* check inputs */
n = A->n ; Ap = A->p ; Ai = A->i ; Ax = A->x ;
for (j = 0 ; j < n ; j++)
{
p = Ap [j] ; /* get current location of col j */
Ap [j] = nz ; /* record new location of col j */
for ( ; p < Ap [j+1] ; p++)
{
if (fkeep (Ai [p], j, Ax ? Ax [p] : 1, other))
{
if (Ax) Ax [nz] = Ax [p] ; /* keep A(i,j) */
Ai [nz++] = Ai [p] ;
}
}
}
Ap [n] = nz ; /* finalize A */
cs_sprealloc (A, 0) ; /* remove extra space from A */
return (nz) ;
}
|
