TESTING/LIN/ztpt06.f(3)

NAME
TESTING/LIN/ztpt06.f

SYNOPSIS

  Functions/Subroutines
subroutine ztpt06 (rcond, rcondc, uplo, diag, n, ap, rwork, rat)
ZTPT06

Function/Subroutine Documentation

  subroutine ztpt06 (double precision rcond, double precision rcondc, character uplo, character diag, integer n, complex*16, dimension( * ) ap, double precision, dimension( * ) rwork, double precision rat)

ZTPT06

Purpose:

     ZTPT06 computes a test ratio comparing RCOND (the reciprocal
     condition number of the triangular matrix A) and RCONDC, the estimate
     computed by ZTPCON.  Information about the triangular matrix is used
     if one estimate is zero and the other is non-zero to decide if
     underflow in the estimate is justified.

Parameters
    RCOND

              RCOND is DOUBLE PRECISION
              The estimate of the reciprocal condition number obtained by
              forming the explicit inverse of the matrix A and computing
              RCOND = 1/( norm(A) * norm(inv(A)) ).

    RCONDC

              RCONDC is DOUBLE PRECISION
              The estimate of the reciprocal condition number computed by
              ZTPCON.

    UPLO

              UPLO is CHARACTER
              Specifies whether the matrix A is upper or lower triangular.
              = 'U':  Upper triangular
              = 'L':  Lower triangular

    DIAG

              DIAG is CHARACTER
              Specifies whether or not the matrix A is unit triangular.
              = 'N':  Non-unit triangular
              = 'U':  Unit triangular

    N

              N is INTEGER
              The order of the matrix A.  N >= 0.

    AP

              AP is COMPLEX*16 array, dimension (N*(N+1)/2)
              The upper or lower triangular matrix A, packed columnwise in
              a linear array.  The j-th column of A is stored in the array
              AP as follows:
              if UPLO = 'U', AP((j-1)*j/2 + i) = A(i,j) for 1<=i<=j;
              if UPLO = 'L',
                 AP((j-1)*(n-j) + j*(j+1)/2 + i-j) = A(i,j) for j<=i<=n.

    RWORK

              RWORK is DOUBLE PRECISION array, dimension (N)

    RAT

              RAT is DOUBLE PRECISION
              The test ratio.  If both RCOND and RCONDC are nonzero,
                 RAT = MAX( RCOND, RCONDC )/MIN( RCOND, RCONDC ) - 1.
              If RAT = 0, the two estimates are exactly the same.

Author
    Univ. of Tennessee

    Univ. of California Berkeley

    Univ. of Colorado Denver

    NAG Ltd.

Definition at line 111 of file ztpt06.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.