subroutine zlartg (F, G, CS, SN, R)
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.
F is COMPLEX*16 The first component of vector to be rotated.G
G is COMPLEX*16 The second component of vector to be rotated.CS
CS is DOUBLE PRECISION The cosine of the rotation.SN
SN is COMPLEX*16 The sine of the rotation.R
R is COMPLEX*16 The nonzero component of the rotated vector.
Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd.Date:
November 2013Further 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.