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sgtts2.f(3)                         LAPACK                         sgtts2.f(3)


NAME

       sgtts2.f -


SYNOPSIS

   Functions/Subroutines
       subroutine sgtts2 (ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)
           SGTTS2 solves a system of linear equations with a tridiagonal
           matrix using the LU factorization computed by sgttrf.

Function/Subroutine Documentation
   subroutine sgtts2 (integerITRANS, integerN, integerNRHS, real, dimension( *
       )DL, real, dimension( * )D, real, dimension( * )DU, real, dimension( *
       )DU2, integer, dimension( * )IPIV, real, dimension( ldb, * )B,
       integerLDB)
       SGTTS2 solves a system of linear equations with a tridiagonal matrix
       using the LU factorization computed by sgttrf.

       Purpose:

            SGTTS2 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 SGTTRF.

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

           D

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

           DU

                     DU is REAL array, dimension (N-1)
                     The (n-1) elements of the first super-diagonal of U.

           DU2

                     DU2 is REAL 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 REAL 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 sgtts2.f.

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

Version 3.4.2                   Sat Nov 16 2013                    sgtts2.f(3)

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