[Routing] A-Star meet-in-the-middle

Andreas Leupin a.leupin at hispeed.ch
Tue Nov 20 20:53:31 GMT 2007


However, I think that the A*-algorithm is not ideal because it is  
absolutely symmetrical around the start/destination - this means that  
routes leading away from the destination are equal than those leading  
into the direction of the destination. On www.leupinfo.ch/OpenGPScout  
I tried to describe an algorithm, which is very similar to A* but  
prefers the routes to the direction of the destination...
Furthermore I prefer to calculate the route from destination to  
start, because the start-point is constantly changing during the  
drive, whereas the destination is stable - therefore, I can use the  
calculations already done, when I leave the precalculated route  
during my drive...
Regards
Andreas

Am 20.11.2007 um 17:24 schrieb Robert (Jamie) Munro:

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> Is there a reason you can't route by doing 2 A-stars  
> simultaneously, one
> from the start and one from the destination, and stop when the 2 meet?
>
> AFAICS, this is likely to be quicker than a normal A-star because the
> recursion will be less broad. I'm not 100% sure though.
>
> Robert (Jamie) Munro
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Andreas Leupin
Kretzgasse 2
CH-5416-Kirchdorf
Tel. P [+41](0)56 282 07 40
        G [+41](0)56 310 39 32
a.leupin at hispeed.ch



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