This seems a single linkage clustering issue: > grouping <- hclust(dist(data.frame(x,y)),"single") > cutree(grouping, h=0.5) [1] 1 1 1 2 3 3 3
Cheers, Marcelino At 13:04 26/10/2010, jgar...@ija.csic.es wrote: >Dear all, >I am wondering if there is a direct function (I cannot find any) in R, to >obtain, a "factor" vector to identify which points could be grouped in a >set, using a specific threshold distance as clustering criterion. > >#e.g, with 7 points with coordinates: > >x <- c(1.01,0.95,1.05,1.03,3.03,2.99,3.04) >y <- c(3.01,3.02,3.04,5.23,2.01,2.02,1.98) > ># and, let's say, distance threshold 0.5, the answer would be: >(1,1,1,2,3,3,3) > ># where the threshold is the maximum distance between any two points for >each cluster > >A better approach would be that threshold could be specified as the >distance between any point in each cluster, and its corresponding center >of mass for that cluster, but I guess this would require some loops. Isn't >it? S, I would be happy enough with the abovementioned approach. > >If there isn't a direct function, don't worry. I'll try to find a solution >computing distances... > >Thanks, >Javier >--- > > > > > > is it possible to load a complete Grass mapset into a raster stack or > > brick > > with a single command? > > > > -- > > View this message in context: > > > http://r-sig-geo.2731867.n2.nabble.com/Grass-and-raster-package-tp5667199p5667199.html > > Sent from the R-sig-geo mailing list archive at Nabble.com. > > > > _______________________________________________ > > R-sig-Geo mailing list > > R-sig-Geo@stat.math.ethz.ch > > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > > > >_______________________________________________ >R-sig-Geo mailing list >R-sig-Geo@stat.math.ethz.ch >https://stat.ethz.ch/mailman/listinfo/r-sig-geo ____________________________________ Marcelino de la Cruz Rot Depto. Biologia Vegetal EUIT Agricola Universidad Politecnica de Madrid tel: 34 + 913365435 ____________________________________ [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo
