ECLiPSe

It seems that the ic-library of ECLiPSe is not powerful enough to
discover inconsistency of
-2*X+8*Y =:= 1, 2*X -8*Y =:= 7. Does anybody have ideas how this can
be remedied? I'm using constraints over Q and Z.


Best regards,
Alexander

AS <Alexander.Serebrenik@cs.kuleuven.ac.be> wrote:
> It seems that the ic-library of ECLiPSe is not powerful enough to
> discover inconsistency of
> -2*X+8*Y =:= 1, 2*X -8*Y =:= 7. Does anybody have ideas how this can
> be remedied? I'm using constraints over Q and Z.


> Best regards,
> Alexander
Dear Alexander,

Pure interval (or bounds) techniques perform very poorly with linear
constraints.  You might be interested in some of the work we have done
aiming to resolve this problem.

C.K. Chiu and J.H.M. Lee. Interval Linear Constraint Solving Using the
Preconditioned Interval Gauss-Seidel Method, {\em Twelfth
International Conference on Logic Programming}, pp.17--32, MIT Press,
Kanagawa, Japan, June, 1995

C.K.~Chiu and J.H.M.~Lee. Efficient Interval Linear Equality Solving
in Constraint Logic Programming, {\em Reliable Computing\/},
8(2), pages 139--174, Kluwer Academic Publishers, 2002

Cheers,
jim

Dear Jim,

Thank you very much!

Alexander