CLANV2(l) ) CLANV2(l)NAME
CLANV2 - compute the Schur factorization of a complex 2-by-2 nonhermi‐
tian matrix in standard form
SYNOPSIS
SUBROUTINE CLANV2( A, B, C, D, RT1, RT2, CS, SN )
REAL CS
COMPLEX A, B, C, D, RT1, RT2, SN
PURPOSE
CLANV2 computes the Schur factorization of a complex 2-by-2 nonhermi‐
tian matrix in standard form:
[ A B ] = [ CS -SN ] [ AA BB ] [ CS SN ]
[ C D ] [ SN CS ] [ 0 DD ] [-SN CS ]
ARGUMENTS
A (input/output) COMPLEX
B (input/output) COMPLEX C (input/output) COMPLEX D
(input/output) COMPLEX On entry, the elements of the input
matrix. On exit, they are overwritten by the elements of the
standardised Schur form.
RT1 (output) COMPLEX
RT2 (output) COMPLEX The two eigenvalues.
CS (output) REAL
SN (output) COMPLEX Parameters of the rotation matrix.
FURTHER DETAILS
Implemented by Mark R. Fahey, May 28, 1999
ScaLAPACK version 1.7 13 August 2001 CLANV2(l)
