Developer Reference

  • 2020.2
  • 07/15/2020
  • Public Content
Contents

?lasq6

Computes one dqd transform in ping-pong form. Used by
?bdsqr
and
?stegr
.

Syntax

call slasq6
(
i0
,
n0
,
z
,
pp
,
dmin
,
dmin1
,
dmin2
,
dn
,
dnm1
,
dnm2
)
call dlasq6
(
i0
,
n0
,
z
,
pp
,
dmin
,
dmin1
,
dmin2
,
dn
,
dnm1
,
dnm2
)
Include Files
  • mkl.fi
Description
The routine
?lasq6
computes one
dqd
(shift equal to zero) transform in ping-pong form, with protection against underflow and overflow.
Input Parameters
i0
INTEGER
. First index.
n0
INTEGER
. Last index.
z
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
.
Array,
DIMENSION
(4
n
).
Z
holds the qd array.
emin
is stored in
z
(4*
n0
)
to avoid an extra argument.
pp
INTEGER
.
pp
=0
for ping,
pp
=1
for pong.
Output Parameters
dmin
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
.
Minimum value of
d
.
dmin1
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
.
Minimum value of
d
, excluding
d
(
n0
).
dmin2
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
.
Minimum value of
d
, excluding
d
(
n0
) and
d
(
n0
-1)
.
dn
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
. Contains
d
(
n0
)
, the last value of
d
.
dnm1
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
. Contains
d
(
n0
-1)
.
dnm2
REAL
for
slasq6
DOUBLE PRECISION
for
dlasq6
. Contains
d
(
n0
-2)
.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizati