[rules-users] [Planner] Travelling Salesman

[Geoffrey De Smet]

You might be disabling "delta score calculation" with your score rules:
   
https://github.com/triceo/DroolingTSP/blob/master/src/main/rules/tspScoreRules.drl
Read
   
http://downloads.jboss.com/drools/docs/5.1.1.34858.FINAL/drools-planner/html_single/index.html#d0e1530

Simulated annealing doesn't work well when it's difficult to find 
solutions which have no hard constraints broken.
I am investing at a fix for that.

Mix in a course-grained MoveFactory (but keep the current one too).

Have you tried the benchmarker to try different tabu search 
configurations against each other?
Property tabu 5 or 7 and Move tabu 7 or 11 usually work well.

HTH

Op 14-02-11 09:34, Lukáš Petrovický schreef:
> Hello,
>
> I've been making myself familiar with Drools Planner and in the process
> of doing so, I've hacked together a simple algorithm for optimizing the
> Travelling Salesman Problem:
>
> https://github.com/triceo/DroolingTSP
>
> At this point, I get a 7 % improvement over a route with 71 stops, which
> was previously assembled using a nearest-neighbor algorithm. The reason
> why the improvement isn't bigger is that I'm stuck with Tabu search only
> - for my use case, simulated annealing doesn't work at all. (Exits
> forcefully after 1 to 7 steps, resulting in only a minimal improvement.)
>
> I'll be interested in any comments and suggestions you might be able to
> provide.
>
> Best regards!
>

-- 
With kind regards,
Geoffrey De Smet