76 lines
1.4 KiB
C
76 lines
1.4 KiB
C
|
|
/* -- 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_ */
|
|
|