On Sun, Nov 4, 2012 at 10:00 PM, Michal D. <michal.dobrog...@gmail.com> wrote: >> A tricky part seems to be that the upper triangle of A corresponds to >> the forward direction in C (the bit in D that selects a row in A is >> also selecting a row in C) while the lower triangle of A corresponds >> to the reverse direction in C. But I'm not seeing anything like this >> in the text of the wikipedia entry. And, if the diagram on the right >> hand side is meant to be an illustration where the constraint is x < y >> then it looks like we do not care about the order of the two >> variables. In other words, if we specify the constraint x < y it >> looks like either x1 < x2 or x2 < x1 is sufficient to satisfy arc >> consistency. In other words, i think we should always use the >> symmetric closure of the constraint. > >> Does this sound valid to you? > > Unfortunately not. There are no values that can satisfy x1<x2 and x2<x1. > If this was the case all csps would have no solutions
I meant x1<x2 OR x2<x1 So symmetric closure was the wrong term for me to use. But I think we want to be using intersection of the relationship with its inverse. Does that sound right to you? Thanks, -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
