DLASQ5(1LAPACK routine (version 3.2)DLASQ5(1)NAME
DLASQ5 - computes one dqds transform in ping-pong form, one version for
IEEE machines another for non IEEE machines
SYNOPSIS
SUBROUTINE DLASQ5( I0, N0, Z, PP, TAU, DMIN, DMIN1, DMIN2, DN, DNM1,
DNM2, IEEE )
LOGICAL IEEE
INTEGER I0, N0, PP
DOUBLE PRECISION DMIN, DMIN1, DMIN2, DN, DNM1, DNM2, TAU
DOUBLE PRECISION Z( * )
PURPOSE
DLASQ5 computes one dqds transform in ping-pong form, one version for
IEEE machines another for non IEEE machines.
ARGUMENTS
I0 (input) INTEGER
First index.
N0 (input) INTEGER
Last index.
Z (input) DOUBLE PRECISION array, dimension ( 4*N )
Z holds the qd array. EMIN is stored in Z(4*N0) to avoid an extra
argument.
PP (input) INTEGER
PP=0 for ping, PP=1 for pong.
TAU (input) DOUBLE PRECISION
This is the shift.
DMIN (output) DOUBLE PRECISION
Minimum value of d. DMIN1 (output) DOUBLE PRECISION Minimum
value of d, excluding D( N0 ). DMIN2 (output) DOUBLE PRECISION
Minimum value of d, excluding D( N0 ) and D( N0-1 ).
DN (output) DOUBLE PRECISION
d(N0), the last value of d.
DNM1 (output) DOUBLE PRECISION
d(N0-1).
DNM2 (output) DOUBLE PRECISION
d(N0-2).
IEEE (input) LOGICAL
Flag for IEEE or non IEEE arithmetic.
LAPACK routine (version 3.2) November 2008 DLASQ5(1)
