SRC/dgtts2.f(3)            Library Functions Manual            SRC/dgtts2.f(3)

NAME
       SRC/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 (integer itrans, integer n, integer nrhs, double
       precision, dimension( * ) dl, double precision, dimension( * ) d,
       double precision, dimension( * ) du, double precision, dimension( * )
       du2, integer, dimension( * ) ipiv, double precision, dimension( ldb, *
       ) b, integer ldb)
       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 (N-1)
                     The (n-1) 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 (N-1)
                     The (n-1) elements of the first super-diagonal of U.

           DU2

                     DU2 is DOUBLE PRECISION array, dimension (N-2)
                     The (n-2) elements of the second super-diagonal 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.

       Definition at line 127 of file dgtts2.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0                 SRC/dgtts2.f(3)