Developer Reference

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

p?ptsv

Syntax

Solves a symmetric or Hermitian positive definite tridiagonal system of linear equations.
call psptsv
(
n
,
nrhs
,
d
,
e
,
ja
,
desca
,
b
,
ib
,
descb
,
work
,
lwork
,
info
)
call pdptsv
(
n
,
nrhs
,
d
,
e
,
ja
,
desca
,
b
,
ib
,
descb
,
work
,
lwork
,
info
)
call pcptsv
(
n
,
nrhs
,
d
,
e
,
ja
,
desca
,
b
,
ib
,
descb
,
work
,
lwork
,
info
)
call pzptsv
(
n
,
nrhs
,
d
,
e
,
ja
,
desca
,
b
,
ib
,
descb
,
work
,
lwork
,
info
)
Include Files
Description
The
p?ptsv
routine
solves a system of linear equations
A
(1:
n
,
ja
:
ja
+
n
-1)*
X
=
B
(
ib
:
ib
+
n
-1, 1:
nrhs
)
,
where
A
(1:
n
,
ja
:
ja
+
n
-1)
is an
n
-by-
n
real tridiagonal symmetric positive definite distributed matrix.
Cholesky factorization is used to factor a reordering of the matrix into
L*L'
.
Optimization Notice
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
This notice covers the following instruction sets: SSE2, SSE4.2, AVX2, AVX-512.
Input Parameters
n
(global)
INTEGER
.
The order of matrix
A
(
n
0)
.
nrhs
(global)
INTEGER
.
The number of right-hand sides; the number of columns of the distributed submatrix
B
(
nrhs
0)
.
d
(local)
REAL
for
psptsv
DOUBLE PRECISON
for
pdptsv
COMPLEX
for
pcptsv
DOUBLE COMPLEX
for
pzptsv
.
Pointer to local part of global vector storing the main diagonal of the matrix.
e
(local)
REAL
for
psptsv
DOUBLE PRECISON
for
pdptsv
COMPLEX
for
pcptsv
DOUBLE COMPLEX
for
pzptsv
.
Pointer to local part of global vector storing the upper diagonal of the matrix. Globally,
du
(n)
is not referenced, and
du
must be aligned with
d
.
ja
(global)
INTEGER
.
The index in the global matrix
A
indicating the start of the matrix to be operated on (which may be either all of
A
or a submatrix of
A
).
desca
(global and local)
INTEGER
array of size
dlen
.
If
1
d
type (
dtype_a
=501