/* crot.f -- translated by f2c (version 20100827).
You must link the resulting object file with libf2c:
on Microsoft Windows system, link with libf2c.lib;
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
or, if you install libf2c.a in a standard place, with -lf2c -lm
-- in that order, at the end of the command line, as in
cc *.o -lf2c -lm
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
http://www.netlib.org/f2c/libf2c.zip
*/
#include "f2c.h"
/* > \brief \b CROT applies a plane rotation with real cosine and complex sine to a pair of complex vectors.
*/
/* =========== DOCUMENTATION =========== */
/* Online html documentation available at */
/* http://www.netlib.org/lapack/explore-html/ */
/* > \htmlonly */
/* > Download CROT + dependencies */
/* > */
/* > [TGZ] */
/* > */
/* > [ZIP] */
/* > */
/* > [TXT] */
/* > \endhtmlonly */
/* Definition: */
/* =========== */
/* SUBROUTINE CROT( N, CX, INCX, CY, INCY, C, S ) */
/* .. Scalar Arguments .. */
/* INTEGER INCX, INCY, N */
/* REAL C */
/* COMPLEX S */
/* .. */
/* .. Array Arguments .. */
/* COMPLEX CX( * ), CY( * ) */
/* .. */
/* > \par Purpose: */
/* ============= */
/* > */
/* > \verbatim */
/* > */
/* > CROT applies a plane rotation, where the cos (C) is real and the */
/* > sin (S) is complex, and the vectors CX and CY are complex. */
/* > \endverbatim */
/* Arguments: */
/* ========== */
/* > \param[in] N */
/* > \verbatim */
/* > N is INTEGER */
/* > The number of elements in the vectors CX and CY. */
/* > \endverbatim */
/* > */
/* > \param[in,out] CX */
/* > \verbatim */
/* > CX is COMPLEX array, dimension (N) */
/* > On input, the vector X. */
/* > On output, CX is overwritten with C*X + S*Y. */
/* > \endverbatim */
/* > */
/* > \param[in] INCX */
/* > \verbatim */
/* > INCX is INTEGER */
/* > The increment between successive values of CX. INCX <> 0. */
/* > \endverbatim */
/* > */
/* > \param[in,out] CY */
/* > \verbatim */
/* > CY is COMPLEX array, dimension (N) */
/* > On input, the vector Y. */
/* > On output, CY is overwritten with -CONJG(S)*X + C*Y. */
/* > \endverbatim */
/* > */
/* > \param[in] INCY */
/* > \verbatim */
/* > INCY is INTEGER */
/* > The increment between successive values of CY. INCX <> 0. */
/* > \endverbatim */
/* > */
/* > \param[in] C */
/* > \verbatim */
/* > C is REAL */
/* > \endverbatim */
/* > */
/* > \param[in] S */
/* > \verbatim */
/* > S is COMPLEX */
/* > C and S define a rotation */
/* > [ C S ] */
/* > [ -conjg(S) C ] */
/* > where C*C + S*CONJG(S) = 1.0. */
/* > \endverbatim */
/* Authors: */
/* ======== */
/* > \author Univ. of Tennessee */
/* > \author Univ. of California Berkeley */
/* > \author Univ. of Colorado Denver */
/* > \author NAG Ltd. */
/* > \ingroup complexOTHERauxiliary */
/* ===================================================================== */
/* Subroutine */ int crot_(integer *n, complex *cx, integer *incx, complex *
cy, integer *incy, real *c__, complex *s)
{
/* System generated locals */
integer i__1, i__2, i__3, i__4;
complex q__1, q__2, q__3, q__4;
/* Builtin functions */
void r_cnjg(complex *, complex *);
/* Local variables */
integer i__, ix, iy;
complex stemp;
/* -- LAPACK auxiliary routine -- */
/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* ===================================================================== */
/* .. Local Scalars .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Parameter adjustments */
--cy;
--cx;
/* 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__) {
i__2 = ix;
q__2.r = *c__ * cx[i__2].r, q__2.i = *c__ * cx[i__2].i;
i__3 = iy;
q__3.r = s->r * cy[i__3].r - s->i * cy[i__3].i, q__3.i = s->r * cy[
i__3].i + s->i * cy[i__3].r;
q__1.r = q__2.r + q__3.r, q__1.i = q__2.i + q__3.i;
stemp.r = q__1.r, stemp.i = q__1.i;
i__2 = iy;
i__3 = iy;
q__2.r = *c__ * cy[i__3].r, q__2.i = *c__ * cy[i__3].i;
r_cnjg(&q__4, s);
i__4 = ix;
q__3.r = q__4.r * cx[i__4].r - q__4.i * cx[i__4].i, q__3.i = q__4.r *
cx[i__4].i + q__4.i * cx[i__4].r;
q__1.r = q__2.r - q__3.r, q__1.i = q__2.i - q__3.i;
cy[i__2].r = q__1.r, cy[i__2].i = q__1.i;
i__2 = ix;
cx[i__2].r = stemp.r, cx[i__2].i = stemp.i;
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__) {
i__2 = i__;
q__2.r = *c__ * cx[i__2].r, q__2.i = *c__ * cx[i__2].i;
i__3 = i__;
q__3.r = s->r * cy[i__3].r - s->i * cy[i__3].i, q__3.i = s->r * cy[
i__3].i + s->i * cy[i__3].r;
q__1.r = q__2.r + q__3.r, q__1.i = q__2.i + q__3.i;
stemp.r = q__1.r, stemp.i = q__1.i;
i__2 = i__;
i__3 = i__;
q__2.r = *c__ * cy[i__3].r, q__2.i = *c__ * cy[i__3].i;
r_cnjg(&q__4, s);
i__4 = i__;
q__3.r = q__4.r * cx[i__4].r - q__4.i * cx[i__4].i, q__3.i = q__4.r *
cx[i__4].i + q__4.i * cx[i__4].r;
q__1.r = q__2.r - q__3.r, q__1.i = q__2.i - q__3.i;
cy[i__2].r = q__1.r, cy[i__2].i = q__1.i;
i__2 = i__;
cx[i__2].r = stemp.r, cx[i__2].i = stemp.i;
/* L30: */
}
return 0;
} /* crot_ */