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/* -- translated by f2c (version 19940927).
You must link the resulting object file with the libraries:
-lf2c -lm (in that order)
*/
#include "f2c.h"
/* Subroutine */ int srot_(integer *n, real *sx, integer *incx, real *sy,
integer *incy, real *c, real *s)
{
/* System generated locals */
integer i__1;
/* Local variables */
static integer i;
static real stemp;
static integer ix, iy;
/* applies a plane rotation.
jack dongarra, linpack, 3/11/78.
modified 12/3/93, array(1) declarations changed to array(*)
Parameter adjustments
Function Body */
#define SY(I) sy[(I)-1]
#define SX(I) sx[(I)-1]
if (*n <= 0) {
return 0;
}
if (*incx == 1 && *incy == 1) {
goto L20;
}
/* code for unequal increments or equal increments not equal
to 1 */
ix = 1;
iy = 1;
if (*incx < 0) {
ix = (-(*n) + 1) * *incx + 1;
}
if (*incy < 0) {
iy = (-(*n) + 1) * *incy + 1;
}
i__1 = *n;
for (i = 1; i <= *n; ++i) {
stemp = *c * SX(ix) + *s * SY(iy);
SY(iy) = *c * SY(iy) - *s * SX(ix);
SX(ix) = stemp;
ix += *incx;
iy += *incy;
/* L10: */
}
return 0;
/* code for both increments equal to 1 */
L20:
i__1 = *n;
for (i = 1; i <= *n; ++i) {
stemp = *c * SX(i) + *s * SY(i);
SY(i) = *c * SY(i) - *s * SX(i);
SX(i) = stemp;
/* L30: */
}
return 0;
} /* srot_ */