
sgtsv.f(3) LAPACK sgtsv.f(3)
NAME
sgtsv.f 
SYNOPSIS
Functions/Subroutines
subroutine sgtsv (N, NRHS, DL, D, DU, B, LDB, INFO)
SGTSV computes the solution to system of linear equations A * X = B for GT matrices
Function/Subroutine Documentation
subroutine sgtsv (integerN, integerNRHS, real, dimension( * )DL, real, dimension( * )D, real,
dimension( * )DU, real, dimension( ldb, * )B, integerLDB, integerINFO)
SGTSV computes the solution to system of linear equations A * X = B for GT matrices
Purpose:
SGTSV solves the equation
A*X = B,
where A is an n by n tridiagonal matrix, by Gaussian elimination with
partial pivoting.
Note that the equation A**T*X = B may be solved by interchanging the
order of the arguments DU and DL.
Parameters:
N
N is INTEGER
The order of the matrix A. N >= 0.
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 REAL array, dimension (N1)
On entry, DL must contain the (n1) subdiagonal elements of
A.
On exit, DL is overwritten by the (n2) elements of the
second superdiagonal of the upper triangular matrix U from
the LU factorization of A, in DL(1), ..., DL(n2).
D
D is REAL array, dimension (N)
On entry, D must contain the diagonal elements of A.
On exit, D is overwritten by the n diagonal elements of U.
DU
DU is REAL array, dimension (N1)
On entry, DU must contain the (n1) superdiagonal elements
of A.
On exit, DU is overwritten by the (n1) elements of the first
superdiagonal of U.
B
B is REAL array, dimension (LDB,NRHS)
On entry, the N by NRHS matrix of right hand side matrix B.
On exit, if INFO = 0, the N by NRHS solution matrix X.
LDB
LDB is INTEGER
The leading dimension of the array B. LDB >= max(1,N).
INFO
INFO is INTEGER
= 0: successful exit
< 0: if INFO = i, the ith argument had an illegal value
> 0: if INFO = i, U(i,i) is exactly zero, and the solution
has not been computed. The factorization has not been
completed unless i = N.
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
September 2012
Definition at line 128 of file sgtsv.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 sgtsv.f(3) 
