From: lro@YP.melb.bull.com (Liam Routt)
Subject: Re: Timetable blues
Organization: Bull HN Information Systems Australia.
Date: Mon, 12 Oct 1992 07:59:36 GMT

u9044140@cs.uow.edu.au (Scot Joseph Wilson) writes:

>braca2@cspyr1.cs.adfa.oz.au (BRAY CHRISTOPHER) writes:
>>There are computer programs that you can buy or write, I believe, that will
>>timetable for you.  A few alterations and I'm sure that you could get a
>>convention going.  I dont know whether the costs would preclude a convention
>>from doing this, but I'm sure a teacher could nick one from his school.
>	I wouldn't even want to start thinking about the actual processing it
>has to do. What will your program do if there is no solution? Go endlessly?
>How close to a perfect soulution can you come to? How do you organise the
>first and second choice for individuals to make up a team? What about those
>people who won't play with certain other people? Or GM's that won't GM certain
>teams due to dislikes or them being their friends?(For fair play's sake?)...

    As it happens, this is one of the fields of computer software I am
currently working in. I work at Bull Information Systems, who have the
language Charme on the market. As far as I know it is the first commercially
available constraint-based operations research programming language. Such
languages are designed, and perfectly suited to, the sort of scheduling
we are talking about.
    Just by luck, I guess, scheduling problems are amongst the hardest for
computers to solve (no flames please!). In general the speed of a computer is
squandered by checking all possible solutions, which can take forever
(literaly). Contratin-based languages operate by reducing the number of
possible choices throughout the process, to avoid checking all the solutions
that are not feasible for one reason or another.  Using this technology you
can solve problems that used to take even powerful computers days, in only
a few minutes. This is an over-simplification, as you can imagine, but for
some problems it really does work miracles, and for many others it makes
possible tasks that had been avoided or done by hand in the past (including
scheduling).
    But Charme costs tens of thousands of dollars for a single liscence, and
requires (at the moment) a unix machine to run. This is big business stuff,
and not freely available (and don't for a moment think that I would "borrow"
it from work - not matter how much I love RPGs).
    I have been working on conventional PC scheduling for some time, but the
program I am working on is designed to assist a human, and works with only
one tournament. It is useful for the Cthulhu Conglomerate, and has got us
past a number of really last-minute panic situations in the past couple of
years, but it is not large enough to handle a whole convention (although I
am working in that direction)
    When I get a spare moment, though, I am always working on using Charme
to schedule tournaments.  Programming in Charme is non-trivial, and it can
be quite hard to express the problem in such a way that it will be able to
take advantage of Charme's power. Once you do it, though, the solutions
just fall out. Suffice it to say that such a scheduling program is possible
using Charme (and not using most conventional methods), but that it can't be
made available any time in the near future.  I hope that by working out how
the problem can be best solved with Charme I will be able to guide my
programming in conventional languages... Or maybe Charme-PC will be able to
function by then..

	So, scheduling is non-trivial.
	Tools which do it are often very expensive.

	By the way, how much would a convnetion organization group really
be willing to spend for a system that met all of (let's say) John Hughes
requirements (as posted the other day) - I want to judge the longer-term
possibilites for the work I'm doing... Charme-PC may be able to do all
this, and the price may come down...  Who knows?

--
						Liam Routt
	"Murder by Pirates is Good!"		Senior Software Engineer
		-The Princess Bride		Bull Information Systems
						Melbourne, AUSTRALIA
Newsgroups: aus.games.roleplay