GNU/Linux |
CentOS 4.8 |
i386 |
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zlargv(l) |
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ZLARGV - generate a vector of complex plane rotations with real cosines, determined by elements of the complex vectors x and y
SUBROUTINE ZLARGV( |
N, X, INCX, Y, INCY, C, INCC ) |
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INTEGER |
INCC, INCX, INCY, N |
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DOUBLE |
PRECISION C( * ) |
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COMPLEX*16 |
X( * ), Y( * ) |
ZLARGV 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 ZLARTG, but
differ from the BLAS1 routine ZROTG):
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.
N (input) INTEGER
The number of plane rotations to be generated.
X (input/output) COMPLEX*16 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*16 array, dimension (1+(N-1)*INCY)
On entry, the vector y. On exit, the sines of the plane rotations.
INCY (input) INTEGER
The increment between elements of Y. INCY > 0.
C (output) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
The cosines of the plane rotations.
INCC (input) INTEGER
The increment between elements of C. INCC > 0.
6-6-96 - Modified with a new algorithm by W. Kahan and J. Demmel
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zlargv(l) | ![]() |