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

NAME
       SRC/dgttrs.f

SYNOPSIS
   Functions/Subroutines
       subroutine dgttrs (trans, n, nrhs, dl, d, du, du2, ipiv, b, ldb, info)
           DGTTRS

Function/Subroutine Documentation
   subroutine dgttrs (character trans, 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, integer info)
       DGTTRS

       Purpose:


            DGTTRS 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
           TRANS

                     TRANS is CHARACTER*1
                     Specifies the form of the system of equations.
                     = 'N':  A * X = B  (No transpose)
                     = 'T':  A**T* X = B  (Transpose)
                     = 'C':  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).

           INFO

                     INFO is INTEGER
                     = 0:  successful exit
                     < 0:  if INFO = -i, the i-th argument had an illegal value

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 136 of file dgttrs.f.

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

LAPACK                          Version 3.12.0                 SRC/dgttrs.f(3)