Provided by: liblapack-doc_3.3.1-1_all bug

NAME

       LAPACK-3 - solves one of the systems of equations  A*X = B or A**T*X = B,

SYNOPSIS

       SUBROUTINE DGTTS2( ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB )

           INTEGER        ITRANS, LDB, N, NRHS

           INTEGER        IPIV( * )

           DOUBLE         PRECISION B( LDB, * ), D( * ), DL( * ), DU( * ), DU2( * )

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.

ARGUMENTS

        ITRANS  (input) 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       (input) INTEGER
                The order of the matrix A.

        NRHS    (input) INTEGER
                The number of right hand sides, i.e., the number of columns
                of the matrix B.  NRHS >= 0.

        DL      (input) DOUBLE PRECISION array, dimension (N-1)
                The (n-1) multipliers that define the matrix L from the
                LU factorization of A.

        D       (input) DOUBLE PRECISION array, dimension (N)
                The n diagonal elements of the upper triangular matrix U from
                the LU factorization of A.

        DU      (input) DOUBLE PRECISION array, dimension (N-1)
                The (n-1) elements of the first super-diagonal of U.

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

        IPIV    (input) 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       (input/output) 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     (input) INTEGER
                The leading dimension of the array B.  LDB >= max(1,N).

 LAPACK auxiliary routine (version 3.2)     April 2011                            DGTTS2(3lapack)