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#include "blas.h"
#ifdef __cplusplus
extern "C" {
#endif
int dscal_(int *n, double *sa, double *sx, int *incx)
{
long int i, m, nincx, nn, iincx;
double ssa;
/* scales a vector by a constant.
uses unrolled loops for increment equal to 1.
jack dongarra, linpack, 3/11/78.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*) */
/* Dereference inputs */
nn = *n;
iincx = *incx;
ssa = *sa;
if (nn > 0 && iincx > 0)
{
if (iincx == 1) /* code for increment equal to 1 */
{
m = nn-4;
for (i = 0; i < m; i += 5)
{
sx[i] = ssa * sx[i];
sx[i+1] = ssa * sx[i+1];
sx[i+2] = ssa * sx[i+2];
sx[i+3] = ssa * sx[i+3];
sx[i+4] = ssa * sx[i+4];
}
for ( ; i < nn; ++i) /* clean-up loop */
sx[i] = ssa * sx[i];
}
else /* code for increment not equal to 1 */
{
nincx = nn * iincx;
for (i = 0; i < nincx; i += iincx)
sx[i] = ssa * sx[i];
}
}
return 0;
} /* dscal_ */
#ifdef __cplusplus
}
#endif