NAME
DLASQ6 - compute one dqd (shift equal to zero) transform in ping-pong form, with protection against underflow and overflow
SYNOPSIS
SUBROUTINE DLASQ6(
I0, N0, Z, PP, DMIN, DMIN1, DMIN2, DN,
DNM1, DNM2 )
DOUBLE
PRECISION DMIN, DMIN1, DMIN2, DN, DNM1, DNM2
PURPOSE
DLASQ6 computes one dqd (shift equal to zero) transform in ping-pong form, with protection against underflow and overflow.
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.
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).
ČLÁNKY DO MAILU