Scroll to navigation

clartg.f(3) LAPACK clartg.f(3)

NAME

clartg.f -

SYNOPSIS

Functions/Subroutines


subroutine clartg (F, G, CS, SN, R)
 
CLARTG generates a plane rotation with real cosine and complex sine.

Function/Subroutine Documentation

subroutine clartg (complexF, complexG, realCS, complexSN, complexR)

CLARTG generates a plane rotation with real cosine and complex sine.
Purpose: 
 CLARTG 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 CROTG, 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.
Parameters:
F 
          F is COMPLEX
          The first component of vector to be rotated.
G 
          G is COMPLEX
          The second component of vector to be rotated.
CS 
          CS is REAL
          The cosine of the rotation.
SN 
          SN is COMPLEX
          The sine of the rotation.
R 
          R is COMPLEX
          The nonzero component of the rotated vector.
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
November 2013
Further Details: 
  3-5-96 - Modified with a new algorithm by W. Kahan and J. Demmel


  This version has a few statements commented out for thread safety
  (machine parameters are computed on each entry). 10 feb 03, SJH.
Definition at line 104 of file clartg.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.
Wed Oct 15 2014 Version 3.4.2