TESTING/LIN/zptt02.f(3)

NAME
TESTING/LIN/zptt02.f

SYNOPSIS

  Functions/Subroutines
subroutine zptt02 (uplo, n, nrhs, d, e, x, ldx, b, ldb, resid)
ZPTT02

Function/Subroutine Documentation

  subroutine zptt02 (character uplo, integer n, integer nrhs, double precision, dimension( * ) d, complex*16, dimension( * ) e, complex*16, dimension( ldx, * ) x, integer ldx, complex*16, dimension( ldb, * ) b, integer ldb, double precision resid)

ZPTT02

Purpose:

     ZPTT02 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
    UPLO

              UPLO is CHARACTER*1
              Specifies whether the superdiagonal or the subdiagonal of the
              tridiagonal matrix A is stored.
              = 'U':  E is the superdiagonal of A
              = 'L':  E is the subdiagonal of A

    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 COMPLEX*16 array, dimension (N-1)
              The (n-1) subdiagonal elements of the tridiagonal matrix A.

    X

              X is COMPLEX*16 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 COMPLEX*16 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 114 of file zptt02.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.