DTRT06 computes a test ratio comparing RCOND (the reciprocal


 condition number of a triangular matrix A) and RCONDC, the estimate


 computed by DTRCON.  Information about the triangular matrix A is


 used if one estimate is zero and the other is non-zero to decide if


 underflow in the estimate is justified.

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


          DTRCON.

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.

A

          A is DOUBLE PRECISION array, dimension (LDA,N)


          The triangular matrix A.  If UPLO = 'U', the leading n by n


          upper triangular part of the array A contains the upper


          triangular matrix, and the strictly lower triangular part of


          A is not referenced.  If UPLO = 'L', the leading n by n lower


          triangular part of the array A contains the lower triangular


          matrix, and the strictly upper triangular part of A is not


          referenced.  If DIAG = 'U', the diagonal elements of A are


          also not referenced and are assumed to be 1.

LDA

          LDA is INTEGER


          The leading dimension of the array A.  LDA >= max(1,N).

WORK

          WORK 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.

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