clartg (l) - Linux Manuals
clartg: generates a plane rotation so that [ CS SN ] [ F ] [ R ] [ __ ]
Command to display clartg manual in Linux: $ man l clartg
NAME
CLARTG - generates a plane rotation so that [ CS SN ] [ F ] [ R ] [ __ ]
SYNOPSIS
- SUBROUTINE CLARTG(
-
F, G, CS, SN, R )
-
REAL
CS
-
COMPLEX
F, G, R, SN
PURPOSE
CLARTG generates a plane rotation so that
[
-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.
ARGUMENTS
- F (input) COMPLEX
-
The first component of vector to be rotated.
- G (input) COMPLEX
-
The second component of vector to be rotated.
- CS (output) REAL
-
The cosine of the rotation.
- SN (output) COMPLEX
-
The sine of the rotation.
- R (output) COMPLEX
-
The nonzero component of the rotated vector.
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.
Pages related to clartg
- clartg (3)
- clartv (l) - applies a vector of complex plane rotations with real cosines to elements of the complex vectors x and y
- clar1v (l) - computes the (scaled) r-th column of the inverse of the sumbmatrix in rows B1 through BN of the tridiagonal matrix L D L^T - sigma I
- clar2v (l) - applies a vector of complex plane rotations with real cosines from both sides to a sequence of 2-by-2 complex Hermitian matrices,
- clarcm (l) - performs a very simple matrix-matrix multiplication
- clarf (l) - applies a complex elementary reflector H to a complex M-by-N matrix C, from either the left or the right
- clarfb (l) - applies a complex block reflector H or its transpose Haq to a complex M-by-N matrix C, from either the left or the right
- clarfg (l) - generates a complex elementary reflector H of order n, such that Haq * ( alpha ) = ( beta ), Haq * H = I
- clarfp (l) - generates a complex elementary reflector H of order n, such that Haq * ( alpha ) = ( beta ), Haq * H = I
- clarft (l) - forms the triangular factor T of a complex block reflector H of order n, which is defined as a product of k elementary reflectors