dtpt06.f3

!>
!> DTPT06 computes a test ratio comparing RCOND (the reciprocal
!> condition number of a triangular matrix A) and RCONDC, the estimate
!> computed by DTPCON.  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
!>          DTPCON.
!> 

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 DOUBLE PRECISION 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.
!> 

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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