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 rou
tine 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.
Man(1) output converted with
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