/*  -- 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 drot_(integer *n, doublereal *dx, integer *incx, 

	doublereal *dy, integer *incy, doublereal *c, doublereal *s)

{

    /* System generated locals */

    integer i__1;

    /* Local variables */

    static integer i;

    static doublereal dtemp;

    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 DY(I) dy[(I)-1]

#define DX(I) dx[(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) {

	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 <= *n; ++i) {

	dtemp = *c * DX(i) + *s * DY(i);

	DY(i) = *c * DY(i) - *s * DX(i);

	DX(i) = dtemp;

/* L30: */

    }

    return 0;

} /* drot_ */