On Mon, May 11, 2009 6:38 pm, Bruce Miller wrote: > Lars Hellström wrote: >> Is there an established OM symbol for "multistep equations" (see >> example below)? If not, would it make sense as part of some official >> content dictionary? > > When I've asked such questions in the past, > I generally got James' (essentially correct) response, > that it is equivalent to a conjunction of relations. Thanks fro the compliment. > I shared your concern that such a multi-something > is easily converted to the conjunction form, but There is a legitimate concern here. But I think if one is really handling such a beast, one wants the ability to mix, e.g. a < b <= c < d. I also like the abilito to annotate that Lars is asking for. > less reliably converted back. Perhaps <OMR> would be > useful here? agreed. > > As James points out, your case seems to > be sort of a proof, or derivation. Each > rhs follows from, can be derived from, is implied > by, is the asymptotic expansion of, ... > it's associated rhs. The set of > relation(-like) operators, and their sensible > sequences is tricky, and in general there isn't > a trivial transitivity. > > The same notation is used as, eg. a < b = c <= d << e, > where there is (seemingly) less hidden semantic, > just a shorthand. > > I suspect there are cases where there other > hidden semantics. > > My main point being, if one _were_ to define > such a symbol, it would seem that more than one > "Multi<something>" would be called for. I suspect, rather, one multi-purpose "reasoning chain" object: the example above could be recast in terms of \subset, or \subgroup or ...
James Davenport Visiting Full Professor, University of Waterloo Otherwise: Hebron & Medlock Professor of Information Technology and Chairman, Powerful Computing WP, University of Bath OpenMath Content Dictionary Editor and Programme Chair, OpenMath 2009 IMU Committee on Electronic Information and Communication _______________________________________________ Om mailing list [email protected] http://openmath.org/mailman/listinfo/om
