Subroutine */
| 19704 | } /* clarft_ */ |
| 19705 | |
| 19706 | /* Subroutine */ int clartg_(complex *f, complex *g, real *cs, complex *sn, |
| 19707 | complex *r__) |
| 19708 | { |
| 19709 | /* System generated locals */ |
| 19710 | integer i__1; |
| 19711 | real r__1, r__2, r__3, r__4, r__5, r__6, r__7, r__8, r__9, r__10; |
| 19712 | complex q__1, q__2, q__3; |
| 19713 | |
| 19714 | /* Local variables */ |
| 19715 | static real d__; |
| 19716 | static integer i__; |
| 19717 | static real f2, g2; |
| 19718 | static complex ff; |
| 19719 | static real di, dr; |
| 19720 | static complex fs, gs; |
| 19721 | static real f2s, g2s, eps, scale; |
| 19722 | static integer count; |
| 19723 | static real safmn2, safmx2; |
| 19724 | extern doublereal slapy2_(real *, real *), slamch_(char *); |
| 19725 | static real safmin; |
| 19726 | |
| 19727 | |
| 19728 | /* |
| 19729 | -- LAPACK auxiliary routine (version 3.2) -- |
| 19730 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 19731 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 19732 | November 2006 |
| 19733 | |
| 19734 | |
| 19735 | Purpose |
| 19736 | ======= |
| 19737 | |
| 19738 | CLARTG generates a plane rotation so that |
| 19739 | |
| 19740 | [ CS SN ] [ F ] [ R ] |
| 19741 | [ __ ] . [ ] = [ ] where CS**2 + |SN|**2 = 1. |
| 19742 | [ -SN CS ] [ G ] [ 0 ] |
| 19743 | |
| 19744 | This is a faster version of the BLAS1 routine CROTG, except for |
| 19745 | the following differences: |
| 19746 | F and G are unchanged on return. |
| 19747 | If G=0, then CS=1 and SN=0. |
| 19748 | If F=0, then CS=0 and SN is chosen so that R is real. |
| 19749 | |
| 19750 | Arguments |
| 19751 | ========= |
| 19752 | |
| 19753 | F (input) COMPLEX |
| 19754 | The first component of vector to be rotated. |
| 19755 | |
| 19756 | G (input) COMPLEX |
| 19757 | The second component of vector to be rotated. |
| 19758 | |
| 19759 | CS (output) REAL |
| 19760 | The cosine of the rotation. |
| 19761 | |
| 19762 | SN (output) COMPLEX |
| 19763 | The sine of the rotation. |