//---------------------------------------------------------------------
// generate a sparse n-vector (v, iv)
// having nzv nonzeros
//
// mark(i) is set to 1 if position i is nonzero.
// mark is all zero on entry and is reset to all zero before exit
// this corrects a performance bug found by John G. Lewis, caused by
// reinitialization of mark on every one of the n calls to sprnvc
//---------------------------------------------------------------------
static void sprnvc(int n, int nz, int nn1, double v[], int iv[])
{
int nzv, ii, i;
double vecelt, vecloc;
nzv = 0;
while (nzv < nz) {
vecelt = randlc(&tran, amult);
//---------------------------------------------------------------------
// generate an integer between 1 and n in a portable manner
//---------------------------------------------------------------------
vecloc = randlc(&tran, amult);
i = icnvrt(vecloc, nn1) + 1;
if (i > n) continue;
//---------------------------------------------------------------------
// was this integer generated already?
//---------------------------------------------------------------------
logical was_gen = false;
for (ii = 0; ii < nzv; ii++) {
if (iv[ii] == i) {
was_gen = true;
break;
}
}
if (was_gen) continue;
v[nzv] = vecelt;
iv[nzv] = i;
nzv = nzv + 1;
}
}
/*---------------------------------------------------------------------
c generate a sparse n-vector (v, iv)
c having nzv nonzeros
c
c mark(i) is set to 1 if position i is nonzero.
c mark is all zero on entry and is reset to all zero before exit
c this corrects a performance bug found by John G. Lewis, caused by
c reinitialization of mark on every one of the n calls to sprnvc
---------------------------------------------------------------------*/
static void sprnvc(
int n,
int nz,
double v[], /* v[1:*] */
int iv[], /* iv[1:*] */
int nzloc[], /* nzloc[1:n] */
int mark[] ) /* mark[1:n] */
{
int nn1;
int nzrow, nzv, ii, i;
double vecelt, vecloc;
nzv = 0;
nzrow = 0;
nn1 = 1;
do {
nn1 = 2 * nn1;
} while (nn1 < n);
/*--------------------------------------------------------------------
c nn1 is the smallest power of two not less than n
c-------------------------------------------------------------------*/
while (nzv < nz) {
vecelt = randlc(&tran, amult);
/*--------------------------------------------------------------------
c generate an integer between 1 and n in a portable manner
c-------------------------------------------------------------------*/
vecloc = randlc(&tran, amult);
i = icnvrt(vecloc, nn1) + 1;
if (i > n) continue;
/*--------------------------------------------------------------------
c was this integer generated already?
c-------------------------------------------------------------------*/
if (mark[i] == 0) {
mark[i] = 1;
nzrow = nzrow + 1;
nzloc[nzrow] = i;
nzv = nzv + 1;
v[nzv] = vecelt;
iv[nzv] = i;
}
}
for (ii = 1; ii <= nzrow; ii++) {
i = nzloc[ii];
mark[i] = 0;
}
}
