Homepage > Man Pages > Category > Subroutines
Homepage > Man Pages > Name > Z

zlaqr1

man page of zlaqr1

zlaqr1:

NAME

SYNOPSIS

SUBROUTINE ZLAQR1( N, H, LDH, S1, S2, V ) COMPLEX*16 S1, S2 INTEGER LDH, N COMPLEX*16 H( LDH, * ), V( * ) COMPLEX*16 ZERO PARAMETER ( ZERO = ( 0.0d0, 0.0d0 ) ) DOUBLE PRECISION RZERO PARAMETER ( RZERO = 0.0d0 ) COMPLEX*16 CDUM, H21S, H31S DOUBLE PRECISION S INTRINSIC ABS, DBLE, DIMAG DOUBLE PRECISION CABS1 CABS1( CDUM ) = ABS( DBLE( CDUM ) ) + ABS( DIMAG( CDUM ) ) IF( N.EQ.2 ) THEN S = CABS1( H( 1, 1 )-S2 ) + CABS1( H( 2, 1 ) ) IF( S.EQ.RZERO ) THEN V( 1 ) = ZERO V( 2 ) = ZERO ELSE H21S = H( 2, 1 ) / S V( 1 ) = H21S*H( 1, 2 ) + ( H( 1, 1 )-S1 )* ( ( H( 1, 1 )-S2 ) / S ) V( 2 ) = H21S*( H( 1, 1 )+H( 2, 2 )-S1-S2 ) END IF ELSE S = CABS1( H( 1, 1 )-S2 ) + CABS1( H( 2, 1 ) ) + CABS1( H( 3, 1 ) ) IF( S.EQ.ZERO ) THEN V( 1 ) = ZERO V( 2 ) = ZERO V( 3 ) = ZERO ELSE H21S = H( 2, 1 ) / S H31S = H( 3, 1 ) / S V( 1 ) = ( H( 1, 1 )-S1 )*( ( H( 1, 1 )-S2 ) / S ) + H( 1, 2 )*H21S + H( 1, 3 )*H31S V( 2 ) = H21S*( H( 1, 1 )+H( 2, 2 )-S1-S2 ) + H( 2, 3 )*H31S V( 3 ) = H31S*( H( 1, 1 )+H( 3, 3 )-S1-S2 ) + H21S*H( 3, 2 ) END IF END IF END
PURPOSE
LAPACK auxiliary routine (versionMarch 2011 ZLAQR1(3)
 
 
 

Copyright © 2011–2018 by topics-of-interest.com . All rights reserved. Hosted by all-inkl.
Contact · Imprint · Privacy

Page generated in 29.32ms.

get-ip.de | HTML, CSS, Javascript, mehr... | information-information.de