ZLARTG(l) ) ZLARTG(l)NAME
ZLARTG - generate a plane rotation so that [ CS SN ] [ F ] [ R ] [ __
]
SYNOPSIS
SUBROUTINE ZLARTG( F, G, CS, SN, R )
DOUBLE PRECISION CS
COMPLEX*16 F, G, R, SN
PURPOSE
ZLARTG generates a plane rotation so that [ CS SN ] [ F ] [ R ] [ __ ]
. [ ] = [ ] where CS**2 + |SN|**2 = 1. [ -SN CS ] [ G ] [
0 ]
This is a faster version of the BLAS1 routine ZROTG, except for the
following differences:
F and G are unchanged on return.
If G=0, then CS=1 and SN=0.
If F=0, then CS=0 and SN is chosen so that R is real.
ARGUMENTS
F (input) COMPLEX*16
The first component of vector to be rotated.
G (input) COMPLEX*16
The second component of vector to be rotated.
CS (output) DOUBLE PRECISION
The cosine of the rotation.
SN (output) COMPLEX*16
The sine of the rotation.
R (output) COMPLEX*16
The nonzero component of the rotated vector.
FURTHER DETAILS
3-5-96 - Modified with a new algorithm by W. Kahan and J. Demmel
LAPACK version 3.0 15 June 2000 ZLARTG(l)
