dptts2.f (3) Linux Manual Page
dptts2.f –
Synopsis
Functions/Subroutines
subroutine dptts2 (N, NRHS, D, E, B, LDB)DPTTS2 solves a tridiagonal system of the form AX=B using the L D LH factorization computed by spttrf.
Function/Subroutine Documentation
subroutine dptts2 (integerN, integerNRHS, double precision, dimension( * )D, double precision, dimension( * )E, double precision, dimension( ldb, * )B, integerLDB)
DPTTS2 solves a tridiagonal system of the form AX=B using the L D LH factorization computed by spttrf. Purpose:
DPTTS2 solves a tridiagonal system of the form
A * X = B
using the L*D*L**T factorization of A computed by DPTTRF. D is a
diagonal matrix specified in the vector D, L is a unit bidiagonal
matrix whose subdiagonal is specified in the vector E, and X and B
are N by NRHS matrices.
Parameters:
- N
N is INTEGER
NRHS
The order of the tridiagonal matrix A. N >= 0.NRHS is INTEGER
D
The number of right hand sides, i.e., the number of columns
of the matrix B. NRHS >= 0.D is DOUBLE PRECISION array, dimension (N)
E
The n diagonal elements of the diagonal matrix D from the
L*D*L**T factorization of A.E is DOUBLE PRECISION array, dimension (N-1)
B
The (n-1) subdiagonal elements of the unit bidiagonal factor
L from the L*D*L**T factorization of A. E can also be regarded
as the superdiagonal of the unit bidiagonal factor U from the
factorization A = U**T*D*U.B is DOUBLE PRECISION array, dimension (LDB,NRHS)
LDB
On entry, the right hand side vectors B for the system of
linear equations.
On exit, the solution vectors, X.LDB is INTEGER
The leading dimension of the array B. LDB >= max(1,N).
Author:
- Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
- September 2012
Definition at line 103 of file dptts2.f.
