Quoting ballibum <[email protected]>: > Hello list, > i´ve got two multipolygon layers ( i call them a and b). Now, I create two > collections, is it possible two get a third collection like: > > collection_c = collection_a.difference(collection_b) > > or must i generate a loop and reduce every feature_a with every feature_b?
No, this is of complexity n x m A quick advise is to create a geometry big_b using the union oberation for all feature_b. For each feature_a, calculate feature_a difference big_b. This is of complexity n + m and will work with large quantities too. > > thanks a lot > balli > > > -- > View this message in context: > http://osgeo-org.1803224.n2.nabble.com/difference-between-layer-a-and-layer-b-tp6358222p6358222.html > Sent from the geotools-gt2-users mailing list archive at Nabble.com. > > ------------------------------------------------------------------------------ > Achieve unprecedented app performance and reliability > What every C/C++ and Fortran developer should know. > Learn how Intel has extended the reach of its next-generation tools > to help boost performance applications - inlcuding clusters. > http://p.sf.net/sfu/intel-dev2devmay > _______________________________________________ > Geotools-gt2-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users > ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program. ------------------------------------------------------------------------------ Achieve unprecedented app performance and reliability What every C/C++ and Fortran developer should know. Learn how Intel has extended the reach of its next-generation tools to help boost performance applications - inlcuding clusters. http://p.sf.net/sfu/intel-dev2devmay _______________________________________________ Geotools-gt2-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
