slartg (l)  Linux Manuals
slartg: generate a plane rotation so that [ CS SN ]
Command to display slartg
manual in Linux: $ man l slartg
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
[
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.
This version has a few statements commented out for thread safety
(machine parameters are computed on each entry). 10 feb 03, SJH.
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