TESTING/LIN/dptt02.f(3)    Library Functions Manual    TESTING/LIN/dptt02.f(3)

NAME
       TESTING/LIN/dptt02.f

SYNOPSIS
   Functions/Subroutines
       subroutine dptt02 (n, nrhs, d, e, x, ldx, b, ldb, resid)
           DPTT02

Function/Subroutine Documentation
   subroutine dptt02 (integer n, integer nrhs, double precision, dimension( *
       ) d, double precision, dimension( * ) e, double precision, dimension(
       ldx, * ) x, integer ldx, double precision, dimension( ldb, * ) b,
       integer ldb, double precision resid)
       DPTT02

       Purpose:


            DPTT02 computes the residual for the solution to a symmetric
            tridiagonal system of equations:
               RESID = norm(B - A*X) / (norm(A) * norm(X) * EPS),
            where EPS is the machine epsilon.

       Parameters
           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 matrices B and X.  NRHS >= 0.

           D

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

           E

                     E is DOUBLE PRECISION array, dimension (N-1)
                     The (n-1) subdiagonal elements of the tridiagonal matrix A.

           X

                     X is DOUBLE PRECISION array, dimension (LDX,NRHS)
                     The n by nrhs matrix of 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 n by nrhs matrix of right hand side vectors B.
                     On exit, B is overwritten with the difference B - A*X.

           LDB

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

           RESID

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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 103 of file dptt02.f.

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

LAPACK                          Version 3.12.0         TESTING/LIN/dptt02.f(3)