dget39.f3

!>
!> DGET39 tests DLAQTR, a routine for solving the real or
!> special complex quasi upper triangular system
!>
!>      op(T)*p = scale*c,
!> or
!>      op(T + iB)*(p+iq) = scale*(c+id),
!>
!> in real arithmetic. T is upper quasi-triangular.
!> If it is complex, then the first diagonal block of T must be
!> 1 by 1, B has the special structure
!>
!>                B = [ b(1) b(2) ... b(n) ]
!>                    [       w            ]
!>                    [           w        ]
!>                    [              .     ]
!>                    [                 w  ]
!>
!> op(A) = A or A', where A' denotes the conjugate transpose of
!> the matrix A.
!>
!> On input, X = [ c ].  On output, X = [ p ].
!>               [ d ]                  [ q ]
!>
!> Scale is an output less than or equal to 1, chosen to avoid
!> overflow in X.
!> This subroutine is specially designed for the condition number
!> estimation in the eigenproblem routine DTRSNA.
!>
!> The test code verifies that the following residual is order 1:
!>
!>      ||(T+i*B)*(x1+i*x2) - scale*(d1+i*d2)||
!>    -----------------------------------------
!>        max(ulp*(||T||+||B||)*(||x1||+||x2||),
!>            (||T||+||B||)*smlnum/ulp,
!>            smlnum)
!>
!> (The (||T||+||B||)*smlnum/ulp term accounts for possible
!>  (gradual or nongradual) underflow in x1 and x2.)
!> 

RMAX

!>          RMAX is DOUBLE PRECISION
!>          Value of the largest test ratio.
!> 

LMAX

!>          LMAX is INTEGER
!>          Example number where largest test ratio achieved.
!> 

NINFO

!>          NINFO is INTEGER
!>          Number of examples where INFO is nonzero.
!> 

KNT

!>          KNT is INTEGER
!>          Total number of examples tested.
!> 

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