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dlagtm.f(3)                         LAPACK                         dlagtm.f(3)

NAME
       dlagtm.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dlagtm (TRANS, N, NRHS, ALPHA, DL, D, DU, X, LDX, BETA, B,
           LDB)
           DLAGTM performs a matrix-matrix product of the form C =
           <alpha>AB+<beta>C, where A is a tridiagonal matrix, B and C are
           rectangular matrices, and <alpha> and <beta> are scalars, which may
           be 0, 1, or -1.

Function/Subroutine Documentation
   subroutine dlagtm (characterTRANS, integerN, integerNRHS, double
       precisionALPHA, double precision, dimension( * )DL, double precision,
       dimension( * )D, double precision, dimension( * )DU, double precision,
       dimension( ldx, * )X, integerLDX, double precisionBETA, double
       precision, dimension( ldb, * )B, integerLDB)
       DLAGTM performs a matrix-matrix product of the form C =
       <alpha>AB+<beta>C, where A is a tridiagonal matrix, B and C are
       rectangular matrices, and <alpha> and <beta> are scalars, which may be
       0, 1, or -1.

       Purpose:

            DLAGTM performs a matrix-vector product of the form

               B := alpha * A * X + beta * B

            where A is a tridiagonal matrix of order N, B and X are N by NRHS
            matrices, and alpha and beta are real scalars, each of which may be
            0., 1., or -1.

       Parameters:
           TRANS

                     TRANS is CHARACTER*1
                     Specifies the operation applied to A.
                     = 'N':  No transpose, B := alpha * A * X + beta * B
                     = 'T':  Transpose,    B := alpha * A'* X + beta * B
                     = 'C':  Conjugate transpose = Transpose

           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 matrices X and B.

           ALPHA

                     ALPHA is DOUBLE PRECISION
                     The scalar alpha.  ALPHA must be 0., 1., or -1.; otherwise,
                     it is assumed to be 0.

           DL

                     DL is DOUBLE PRECISION array, dimension (N-1)
                     The (n-1) sub-diagonal elements of T.

           D

                     D is DOUBLE PRECISION array, dimension (N)
                     The diagonal elements of T.

           DU

                     DU is DOUBLE PRECISION array, dimension (N-1)
                     The (n-1) super-diagonal elements of T.

           X

                     X is DOUBLE PRECISION array, dimension (LDX,NRHS)
                     The N by NRHS matrix X.

           LDX

                     LDX is INTEGER
                     The leading dimension of the array X.  LDX >= max(N,1).

           BETA

                     BETA is DOUBLE PRECISION
                     The scalar beta.  BETA must be 0., 1., or -1.; otherwise,
                     it is assumed to be 1.

           B

                     B is DOUBLE PRECISION array, dimension (LDB,NRHS)
                     On entry, the N by NRHS matrix B.
                     On exit, B is overwritten by the matrix expression
                     B := alpha * A * X + beta * B.

           LDB

                     LDB is INTEGER
                     The leading dimension of the array B.  LDB >= max(N,1).

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 145 of file dlagtm.f.

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

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