TESTING/LIN/dgtt02.f(3)    Library Functions Manual    TESTING/LIN/dgtt02.f(3)

NAME
       TESTING/LIN/dgtt02.f

SYNOPSIS
   Functions/Subroutines
       subroutine dgtt02 (trans, n, nrhs, dl, d, du, x, ldx, b, ldb, resid)
           DGTT02

Function/Subroutine Documentation
   subroutine dgtt02 (character trans, integer n, integer nrhs, double
       precision, dimension( * ) dl, double precision, dimension( * ) d,
       double precision, dimension( * ) du, double precision, dimension( ldx,
       * ) x, integer ldx, double precision, dimension( ldb, * ) b, integer
       ldb, double precision resid)
       DGTT02

       Purpose:


            DGTT02 computes the residual for the solution to a tridiagonal
            system of equations:
               RESID = norm(B - op(A)*X) / (norm(op(A)) * norm(X) * EPS),
            where EPS is the machine epsilon.
            The norm used is the 1-norm.

       Parameters
           TRANS

                     TRANS is CHARACTER
                     Specifies the form of the residual.
                     = 'N':  B - A    * X  (No transpose)
                     = 'T':  B - A**T * X  (Transpose)
                     = 'C':  B - A**H * X  (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 B and X.  NRHS >= 0.

           DL

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

           D

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

           DU

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

           X

                     X is DOUBLE PRECISION array, dimension (LDX,NRHS)
                     The computed solution vectors X.

           LDX

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

           B

                     B is DOUBLE PRECISION array, dimension (LDB,NRHS)
                     On entry, the right hand side vectors for the system of
                     linear equations.
                     On exit, B is overwritten with the difference B - op(A)*X.

           LDB

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

           RESID

                     RESID is DOUBLE PRECISION
                     norm(B - op(A)*X) / (norm(op(A)) * norm(X) * EPS)

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 123 of file dgtt02.f.

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

LAPACK                          Version 3.12.0         TESTING/LIN/dgtt02.f(3)