CLARGV(l) ) CLARGV(l)NAME
CLARGV - generate a vector of complex plane rotations with real
cosines, determined by elements of the complex vectors x and y
SYNOPSIS
SUBROUTINE CLARGV( N, X, INCX, Y, INCY, C, INCC )
INTEGER INCC, INCX, INCY, N
REAL C( * )
COMPLEX X( * ), Y( * )
PURPOSE
CLARGV generates a vector of complex plane rotations with real cosines,
determined by elements of the complex vectors x and y. For i =
1,2,...,n
( c(i)s(i) ) ( x(i) ) = ( r(i) )
( -conjg(s(i)) c(i) ) ( y(i) ) = ( 0 )
where c(i)**2 + ABS(s(i))**2 = 1
The following conventions are used (these are the same as in CLARTG,
but differ from the BLAS1 routine CROTG):
If y(i)=0, then c(i)=1 and s(i)=0.
If x(i)=0, then c(i)=0 and s(i) is chosen so that r(i) is real.
ARGUMENTS
N (input) INTEGER
The number of plane rotations to be generated.
X (input/output) COMPLEX array, dimension (1+(N-1)*INCX)
On entry, the vector x. On exit, x(i) is overwritten by r(i),
for i = 1,...,n.
INCX (input) INTEGER
The increment between elements of X. INCX > 0.
Y (input/output) COMPLEX array, dimension (1+(N-1)*INCY)
On entry, the vector y. On exit, the sines of the plane rota‐
tions.
INCY (input) INTEGER
The increment between elements of Y. INCY > 0.
C (output) REAL array, dimension (1+(N-1)*INCC)
The cosines of the plane rotations.
INCC (input) INTEGER
The increment between elements of C. INCC > 0.
FURTHER DETAILS
6-6-96 - Modified with a new algorithm by W. Kahan and J. Demmel
LAPACK version 3.0 15 June 2000 CLARGV(l)
