On Fri, 8 Jan 2010 10:11:20 +0100 Hans-Jörg Bibiko <bib...@eva.mpg.de> wrote: > I've a tiny question. Is there an annotated river dataset available? > By 'annotated' I mean that rivers are ranked by a sort of > relevance/size/length or whatever. The problem is that I have an huge > SpatialLines object called 'rivers' which shows ~23200 rivers but I > have to draw a map which only shows the most largest ones (let's say > 100 to 150) plus one to three rivers for a country.
How about using the 'SpatialLinesLengths' function? Try get the 100 largest rivers, you can use big.rivers=rivers[rev(order(SpatialLineLengths(rivers)))[1:100],] 'SpatialLinesLengths' may have a bug, though. At least for one of my data, it gives a 'non-finite line lengths' error message on one of the (finite!) lines. -- Karl Ove Hufthammer _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo
