SLARTG(l) ) SLARTG(l)NAME
SLARTG - generate a plane rotation so that [ CS SN ]
SYNOPSIS
SUBROUTINE SLARTG( F, G, CS, SN, R )
REAL CS, F, G, R, SN
PURPOSE
SLARTG generate a plane rotation so that [ CS SN ] . [ F ] = [ R ]
where CS**2 + SN**2 = 1. [ -SN CS ] [ G ] [ 0 ]
This is a slower, more accurate version of the BLAS1 routine SROTG,
with the following other differences:
F and G are unchanged on return.
If G=0, then CS=1 and SN=0.
If F=0 and (G .ne. 0), then CS=0 and SN=1 without doing any
floating point operations (saves work in SBDSQR when
there are zeros on the diagonal).
If F exceeds G in magnitude, CS will be positive.
ARGUMENTS
F (input) REAL
The first component of vector to be rotated.
G (input) REAL
The second component of vector to be rotated.
CS (output) REAL
The cosine of the rotation.
SN (output) REAL
The sine of the rotation.
R (output) REAL
The nonzero component of the rotated vector.
LAPACK version 3.0 15 June 2000 SLARTG(l)
