mirror of
https://github.com/opencv/opencv.git
synced 2024-12-19 03:58:31 +08:00
74 lines
1.4 KiB
C
74 lines
1.4 KiB
C
#include "clapack.h"
|
|
|
|
/* Subroutine */ int drot_(integer *n, doublereal *dx, integer *incx,
|
|
doublereal *dy, integer *incy, doublereal *c__, doublereal *s)
|
|
{
|
|
/* System generated locals */
|
|
integer i__1;
|
|
|
|
/* Local variables */
|
|
integer i__, ix, iy;
|
|
doublereal dtemp;
|
|
|
|
/* .. Scalar Arguments .. */
|
|
/* .. */
|
|
/* .. Array Arguments .. */
|
|
/* .. */
|
|
|
|
/* Purpose */
|
|
/* ======= */
|
|
|
|
/* applies a plane rotation. */
|
|
/* jack dongarra, linpack, 3/11/78. */
|
|
/* modified 12/3/93, array(1) declarations changed to array(*) */
|
|
|
|
|
|
/* .. Local Scalars .. */
|
|
/* .. */
|
|
/* Parameter adjustments */
|
|
--dy;
|
|
--dx;
|
|
|
|
/* Function Body */
|
|
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__ <= i__1; ++i__) {
|
|
dtemp = *c__ * dx[ix] + *s * dy[iy];
|
|
dy[iy] = *c__ * dy[iy] - *s * dx[ix];
|
|
dx[ix] = dtemp;
|
|
ix += *incx;
|
|
iy += *incy;
|
|
/* L10: */
|
|
}
|
|
return 0;
|
|
|
|
/* code for both increments equal to 1 */
|
|
|
|
L20:
|
|
i__1 = *n;
|
|
for (i__ = 1; i__ <= i__1; ++i__) {
|
|
dtemp = *c__ * dx[i__] + *s * dy[i__];
|
|
dy[i__] = *c__ * dy[i__] - *s * dx[i__];
|
|
dx[i__] = dtemp;
|
|
/* L30: */
|
|
}
|
|
return 0;
|
|
} /* drot_ */
|