Developer Reference

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

?ptsv

Computes the solution to the system of linear equations with a symmetric or Hermitian positive definite tridiagonal coefficient matrix A and multiple right-hand sides.

Syntax

call sptsv
(
n
,
nrhs
,
d
,
e
,
b
,
ldb
,
info
)
call dptsv
(
n
,
nrhs
,
d
,
e
,
b
,
ldb
,
info
)
call cptsv
(
n
,
nrhs
,
d
,
e
,
b
,
ldb
,
info
)
call zptsv
(
n
,
nrhs
,
d
,
e
,
b
,
ldb
,
info
)
call ptsv
(
d
,
e
,
b
[
,
info
]
)
Include Files
  • mkl.fi
    ,
    lapack.f90
Description
The routine solves for
X
the real or complex system of linear equations
A*X
=
B
, where
A
is an
n
-by-
n
symmetric/Hermitian positive-definite tridiagonal matrix, the columns of matrix
B
are individual right-hand sides, and the columns of
X
are the corresponding solutions.
A
is factored as
A
=
L*D*L
T
(real flavors) or
A
=
L*D*L
H
(complex flavors), and the factored form of
A
is then used to solve the system of equations
A*X
=
B
.
Input Parameters
n
INTEGER
.
The order of matrix
A
;
n
0.
nrhs
INTEGER
.
The number of right-hand sides, the number of columns in
B
;
nrhs
0
.
d
REAL
for single precision flavors
DOUBLE PRECISION
for double precision flavors.
Array, dimension at least
max(1,
n
)
. Contains the diagonal elements of the tridiagonal matrix
A
.
e
,
b
REAL
for
sptsv
DOUBLE PRECISION
for
dptsv
COMPLEX
for
cptsv
DOUBLE COMPLEX
for
zptsv
.
Arrays:
e
(size
n
- 1),
b
(size
ldb
by *)
. The array
e
contains the
(
n
- 1)
subdiagonal elements of
A
.
The array
b
contains the matrix
B
whose columns are the right-hand sides for the systems of equations.
The second dimension of
b
must be at least
max(1,
nrhs
)
.
ldb
INTEGER
.
The leading dimension of
b
;
ldb
max(1,
n
)
.
Output Parameters