How do they create route map software, and GPS software?

Question

Hi there
I am a software engineer, and there is one thing that has always puzzled me, and that is how they create route map software, such as that found on aa.com

Does anyone have any links to technical white papaers ont he subject, and the theory behind it

cheers

J

Answer 1

Look up 'random walk', 'route optimisation algorithms', 'trial and error algorithms', etc. etc.

Essentially, between any 2 points there are only a limited number of possible routes .. especially if the algorithum selects Motorways over A roards, A over B and B over unclassified ...

This can be done by assigning different 'costs' to each type of road .. the s/w could start by costing the 'most direct' route and them make random changes in an attempt to reduce the 'cost' ..

Answer 2

Google maps are beautiful nicely, in spite of the incontrovertible fact that I choose there became into as quickly as an piece of digital mail cope with to record the occasional errors. "highway point" on Google Maps in some US cities, like in ny, is powerful.