Developer Reference

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

?laed6

Used by
sstedc
/
dstedc
. Computes one Newton step in solution of the secular equation.

Syntax

call slaed6
(
kniter
,
orgati
,
rho
,
d
,
z
,
finit
,
tau
,
info
)
call dlaed6
(
kniter
,
orgati
,
rho
,
d
,
z
,
finit
,
tau
,
info
)
Include Files
  • mkl.fi
Description
The routine computes the positive or negative root (closest to the origin) of
Equation
It is assumed that if
orgati
=
.TRUE.
the root is between
d
(2) and
d
(3);otherwise it is between
d
(1) and
d
(2) This routine is called by
?laed4
when necessary. In most cases, the root sought is the smallest in magnitude, though it might not be in some extremely rare situations.
Input Parameters
kniter
INTEGER
.
Refer to
?laed4
for its significance.
orgati
LOGICAL
.
If
orgati
=
.TRUE.
, the needed root is between
d
(2) and
d
(3); otherwise it is between
d
(1) and
d
(2). See
?laed4
for further details.
rho
REAL
for
slaed6
DOUBLE PRECISION
for
dlaed6
Refer to the equation for
f
(
x
) above.
d
,
z
REAL
for
slaed6
DOUBLE PRECISION
for
dlaed6
Arrays, dimension (3) each.
The array
d
satisfies
d
(1) <
d
(2) <
d
(3)
.
Each of the elements in the array
z
must be positive.
finit
REAL
for
slaed6
DOUBLE PRECISION
for
dlaed6
The value of
f
(
x
) at 0. It is more accurate than the one evaluated inside this routine (if someone wants to do so).
Output Parameters
tau
REAL
for
slaed6
DOUBLE PRECISION
for
dlaed6
The root of the equation for
f
(
x
).
info
INTEGER
.
If
info
= 0
, the execution is successful.
If
info
= 1
, failure to converge.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804