#include "blaswrap.h"
#include "f2c.h"

/* Subroutine */ int dlargv_(integer *n, doublereal *x, integer *incx, 
	doublereal *y, integer *incy, doublereal *c__, integer *incc)
{
/*  -- LAPACK auxiliary routine (version 3.0) --   
       Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
       Courant Institute, Argonne National Lab, and Rice University   
       June 30, 1999   


    Purpose   
    =======   

    DLARGV generates a vector of real plane rotations, determined by   
    elements of the real vectors x and y. For i = 1,2,...,n   

       (  c(i)  s(i) ) ( x(i) ) = ( a(i) )   
       ( -s(i)  c(i) ) ( y(i) ) = (   0  )   

    Arguments   
    =========   

    N       (input) INTEGER   
            The number of plane rotations to be generated.   

    X       (input/output) DOUBLE PRECISION array,   
                           dimension (1+(N-1)*INCX)   
            On entry, the vector x.   
            On exit, x(i) is overwritten by a(i), for i = 1,...,n.   

    INCX    (input) INTEGER   
            The increment between elements of X. INCX > 0.   

    Y       (input/output) DOUBLE PRECISION array,   
                           dimension (1+(N-1)*INCY)   
            On entry, the vector y.   
            On exit, the sines of the plane rotations.   

    INCY    (input) INTEGER   
            The increment between elements of Y. INCY > 0.   

    C       (output) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)   
            The cosines of the plane rotations.   

    INCC    (input) INTEGER   
            The increment between elements of C. INCC > 0.   

    =====================================================================   


       Parameter adjustments */
    /* System generated locals */
    integer i__1;
    /* Builtin functions */
    double sqrt(doublereal);
    /* Local variables */
    static doublereal f, g;
    static integer i__;
    static doublereal t;
    static integer ic, ix, iy;
    static doublereal tt;

    --c__;
    --y;
    --x;

    /* Function Body */
    ix = 1;
    iy = 1;
    ic = 1;
    i__1 = *n;
    for (i__ = 1; i__ <= i__1; ++i__) {
	f = x[ix];
	g = y[iy];
	if (g == 0.) {
	    c__[ic] = 1.;
	} else if (f == 0.) {
	    c__[ic] = 0.;
	    y[iy] = 1.;
	    x[ix] = g;
	} else if (abs(f) > abs(g)) {
	    t = g / f;
	    tt = sqrt(t * t + 1.);
	    c__[ic] = 1. / tt;
	    y[iy] = t * c__[ic];
	    x[ix] = f * tt;
	} else {
	    t = f / g;
	    tt = sqrt(t * t + 1.);
	    y[iy] = 1. / tt;
	    c__[ic] = t * y[iy];
	    x[ix] = g * tt;
	}
	ic += *incc;
	iy += *incy;
	ix += *incx;
/* L10: */
    }
    return 0;

/*     End of DLARGV */

} /* dlargv_ */

