opencv/3rdparty/lapack/sscal.c

83 lines
1.6 KiB
C

#include "clapack.h"
/* Subroutine */ int sscal_(integer *n, real *sa, real *sx, integer *incx)
{
/* System generated locals */
integer i__1, i__2;
/* Local variables */
integer i__, m, mp1, nincx;
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* 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(*) */
/* .. Local Scalars .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* Parameter adjustments */
--sx;
/* Function Body */
if (*n <= 0 || *incx <= 0) {
return 0;
}
if (*incx == 1) {
goto L20;
}
/* code for increment not equal to 1 */
nincx = *n * *incx;
i__1 = nincx;
i__2 = *incx;
for (i__ = 1; i__2 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__2) {
sx[i__] = *sa * sx[i__];
/* L10: */
}
return 0;
/* code for increment equal to 1 */
/* clean-up loop */
L20:
m = *n % 5;
if (m == 0) {
goto L40;
}
i__2 = m;
for (i__ = 1; i__ <= i__2; ++i__) {
sx[i__] = *sa * sx[i__];
/* L30: */
}
if (*n < 5) {
return 0;
}
L40:
mp1 = m + 1;
i__2 = *n;
for (i__ = mp1; i__ <= i__2; i__ += 5) {
sx[i__] = *sa * sx[i__];
sx[i__ + 1] = *sa * sx[i__ + 1];
sx[i__ + 2] = *sa * sx[i__ + 2];
sx[i__ + 3] = *sa * sx[i__ + 3];
sx[i__ + 4] = *sa * sx[i__ + 4];
/* L50: */
}
return 0;
} /* sscal_ */