DLASQ5(3S)DLASQ5(3S)NAMEDLASQ5 - compute 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( * )
IMPLEMENTATION
These routines are part of the SCSL Scientific Library and can be loaded
using either the -lscs or the -lscs_mp option. The -lscs_mp option
directs the linker to use the multi-processor version of the library.
When linking to SCSL with -lscs or -lscs_mp, the default integer size is
4 bytes (32 bits). Another version of SCSL is available in which integers
are 8 bytes (64 bits). This version allows the user access to larger
memory sizes and helps when porting legacy Cray codes. It can be loaded
by using the -lscs_i8 option or the -lscs_i8_mp option. A program may use
only one of the two versions; 4-byte integer and 8-byte integer library
calls cannot be mixed.
PURPOSEDLASQ5 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.
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DLASQ5(3S)DLASQ5(3S)
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.
SEE ALSOINTRO_LAPACK(3S), INTRO_SCSL(3S)
This man page is available only online.
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