
dgtts2.f(3) LAPACK dgtts2.f(3)
NAME
dgtts2.f 
SYNOPSIS
Functions/Subroutines
subroutine dgtts2 (ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)
DGTTS2 solves a system of linear equations with a tridiagonal matrix using the LU
factorization computed by sgttrf.
Function/Subroutine Documentation
subroutine dgtts2 (integerITRANS, integerN, integerNRHS, double precision, dimension( * )DL,
double precision, dimension( * )D, double precision, dimension( * )DU, double precision,
dimension( * )DU2, integer, dimension( * )IPIV, double precision, dimension( ldb, * )B,
integerLDB)
DGTTS2 solves a system of linear equations with a tridiagonal matrix using the LU
factorization computed by sgttrf.
Purpose:
DGTTS2 solves one of the systems of equations
A*X = B or A**T*X = B,
with a tridiagonal matrix A using the LU factorization computed
by DGTTRF.
Parameters:
ITRANS
ITRANS is INTEGER
Specifies the form of the system of equations.
= 0: A * X = B (No transpose)
= 1: A**T* X = B (Transpose)
= 2: A**T* X = B (Conjugate transpose = Transpose)
N
N is INTEGER
The order of the matrix A.
NRHS
NRHS is INTEGER
The number of right hand sides, i.e., the number of columns
of the matrix B. NRHS >= 0.
DL
DL is DOUBLE PRECISION array, dimension (N1)
The (n1) multipliers that define the matrix L from the
LU factorization of A.
D
D is DOUBLE PRECISION array, dimension (N)
The n diagonal elements of the upper triangular matrix U from
the LU factorization of A.
DU
DU is DOUBLE PRECISION array, dimension (N1)
The (n1) elements of the first superdiagonal of U.
DU2
DU2 is DOUBLE PRECISION array, dimension (N2)
The (n2) elements of the second superdiagonal of U.
IPIV
IPIV is INTEGER array, dimension (N)
The pivot indices; for 1 <= i <= n, row i of the matrix was
interchanged with row IPIV(i). IPIV(i) will always be either
i or i+1; IPIV(i) = i indicates a row interchange was not
required.
B
B is DOUBLE PRECISION array, dimension (LDB,NRHS)
On entry, the matrix of right hand side vectors B.
On exit, B is overwritten by the solution vectors X.
LDB
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 129 of file dgtts2.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 dgtts2.f(3) 
