mhm.. well, you could run a test... And avoiding 4 million tests does not seem to be possible.
And not sure if this helps, you, but - buffering is a fairly costly operation (and you should define also the number of points for a quarter circle segment, e.g. the result for buffering a point) - if you have a fairly simple polygon describing the area limits (or is it all linestrings? ... I also did not completely understand what you LineString is), then a point-in-polygon test can be very fast but Martin D. my correct me here. - there is also the option to do some classification/trajectory estimation based on previous data for one car (Kalman-filtering) to see if you need to do some testing (maybe you car did not move at all... so the location-difference has not changed). But I guess the processing of 4 million units is simpler/faster? - finally splitting your data/fleet to contact only a certain server, as form of parallel processing is an option too? stefan Am 26.08.13 13:56, schrieb André Salvati: > Hi Stephan, > > thanks for your answer. > > This would be an useful solution for some batch processing that we do. > > However, I meant that I'm receiving 4 million positions in realtime from > these vehicles (6000) every day, so the app must process one-by-one and > generates alerts when some of them cross the boundaries. In this case, > you would go with 1), 2) or is there another option? > > > > > 2013/8/26 Stefan Steiniger <[email protected] <mailto:[email protected]>> > > Hi Andre, > > if possible, you should use a spatial index, to do some pre-filtering. > JTS comes with a Quadtree and R-Tree (STRtree) implemetation. One is > updatable while the other not (not sure though, which one). > A spatial index allows you to retrieve only those objects from a > dataset, that are fairly close/near by. > > Do you have objects that do not move around?, What are your 4 Million > objects? > > Also could you not buffer your objects only once and then store them? > > best, > stefan > > Am 26.08.13 13:21, schrieb André Salvati: > > Hi, > > > > I'm a beginner with JTS and this is my first post here. > > > > We've been working with geofences for a vehicle tracking app and > I would > > like to know what solution could give me a lower CPU consumption. > > > > 1) Calculate and store a Buffered Area (100 meters) from a LineString > > object. Run 4 million times if my vehicle positions are inside or not > > that precalculated with contains() method. > > > > 2) Run 4 million times isWithinDistance() method from LineString for > > each position. > > > > Are there another options? > > > > Thanks. > > > > > > > > ------------------------------------------------------------------------------ > > Introducing Performance Central, a new site from SourceForge and > > AppDynamics. Performance Central is your source for news, insights, > > analysis and resources for efficient Application Performance > Management. > > Visit us today! > > > > http://pubads.g.doubleclick.net/gampad/clk?id=48897511&iu=/4140/ostg.clktrk > > > > > > > > _______________________________________________ > > Jts-topo-suite-user mailing list > > [email protected] > <mailto:[email protected]> > > https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user > > > > > ------------------------------------------------------------------------------ > Introducing Performance Central, a new site from SourceForge and > AppDynamics. Performance Central is your source for news, insights, > analysis and resources for efficient Application Performance Management. > Visit us today! > > http://pubads.g.doubleclick.net/gampad/clk?id=48897511&iu=/4140/ostg.clktrk > _______________________________________________ > Jts-topo-suite-user mailing list > [email protected] > <mailto:[email protected]> > https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user > > ------------------------------------------------------------------------------ Introducing Performance Central, a new site from SourceForge and AppDynamics. Performance Central is your source for news, insights, analysis and resources for efficient Application Performance Management. Visit us today! http://pubads.g.doubleclick.net/gampad/clk?id=48897511&iu=/4140/ostg.clktrk _______________________________________________ Jts-topo-suite-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user
