"And when travelling 700-1000 km, an extra theoretical(!) 1-2 minutes at the start or in the end (city to city via long motorways), is negligible in case of the above mentioned or a traffic jam."
And don't forget the extra tank stop at a busy fuel station followed by a visit to a busy toilet, especially with small children. :) Op wo 28 nov. 2018 om 17:23 schreef Harry van der Wolf <[email protected]>: > This can be an extremely long answer, so I only give the most briefest > explanation possible with 2 examples. > > OsmAnd, like 95% of the navigation apps, use the A* "pathfinding" > algorithm. When using a heuristic coefficient of 1.0, the algorithm really > uses every path in it's calculation. Theoretically that gives the 100% > perfect route, but is of course very slow and uses a lot of memory: hence > the problem that only shorter routes can be caclulated. > Increasing the heuristic coefficient to values of 1.1 ~ 1.5, makes the > algorithm skip paths that lead to "higher costs". That makes the algorithm > much faster and use less memory, but in theory you can miss the 100% > perfect route in case the fastest route contains a small, slow path > (increasing cost), but possibly followed by very fast motorways. > However, a value of 1.2 ~ 1.4 is really good for car navigation. > The OsmAnd development team on the other hand has chosen to always > calculate the 100% (theoretical) perfect path by using the 1.0 value. > Like I mentioned: your perfect path can contain a red traffic light or a > very busy intersection, and then a less perfect path can be (much) faster. > And when travelling 700-1000 km, an extra theoretical(!) 1-2 minutes at > the start or in the end (city to city via long motorways), is negligible in > case of the above mentioned or a traffic jam. > > Please read this article at Wikipedia: > https://en.wikipedia.org/wiki/A*_search_algorithm > You can find more articles once you know to search for A* algorithm (or > Dijkstra algorithm: the original) > > Harry > > Op wo 28 nov. 2018 om 13:56 schreef Stefan Monnier < > [email protected]>: > >> > I also use a heuristicCoefficient="1.4" since several years following >> the >> > example of Harry van der Wolf, which makes the calculation of routing >> much >> > faster. I like it! >> >> BTW, what does this magic button do? >> >> >> Stefan >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Osmand" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > -- You received this message because you are subscribed to the Google Groups "Osmand" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
