TESTING/LIN/dppt02.f(3)    Library Functions Manual    TESTING/LIN/dppt02.f(3)

NAME
       TESTING/LIN/dppt02.f

SYNOPSIS
   Functions/Subroutines
       subroutine dppt02 (uplo, n, nrhs, a, x, ldx, b, ldb, rwork, resid)
           DPPT02

Function/Subroutine Documentation
   subroutine dppt02 (character uplo, integer n, integer nrhs, double
       precision, dimension( * ) a, double precision, dimension( ldx, * ) x,
       integer ldx, double precision, dimension( ldb, * ) b, integer ldb,
       double precision, dimension( * ) rwork, double precision resid)
       DPPT02

       Purpose:


           !>
           !> DPPT02 computes the residual in the solution of a symmetric system
           !> of linear equations  A*x = b  when packed storage is used for the
           !> coefficient matrix.  The ratio computed is
           !>
           !>    RESID = norm(B - A*X) / ( norm(A) * norm(X) * EPS),
           !>
           !> where EPS is the machine precision.
           !>

       Parameters
           UPLO

           !>          UPLO is CHARACTER*1
           !>          Specifies whether the upper or lower triangular part of the
           !>          symmetric matrix A is stored:
           !>          = 'U':  Upper triangular
           !>          = 'L':  Lower triangular
           !>

           N

           !>          N is INTEGER
           !>          The number of rows and columns of the matrix A.  N >= 0.
           !>

           NRHS

           !>          NRHS is INTEGER
           !>          The number of columns of B, the matrix of right hand sides.
           !>          NRHS >= 0.
           !>

           A

           !>          A is DOUBLE PRECISION array, dimension (N*(N+1)/2)
           !>          The original symmetric matrix A, stored as a packed
           !>          triangular matrix.
           !>

           X

           !>          X is DOUBLE PRECISION array, dimension (LDX,NRHS)
           !>          The computed solution vectors for the system of linear
           !>          equations.
           !>

           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 - A*X.
           !>

           LDB

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

           RWORK

           !>          RWORK is DOUBLE PRECISION array, dimension (N)
           !>

           RESID

           !>          RESID is DOUBLE PRECISION
           !>          The maximum over the number of right hand sides of
           !>          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 120 of file dppt02.f.

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

LAPACK                          Version 3.12.0         TESTING/LIN/dppt02.f(3)