I have a list of coordinates that each corresponds to the center of polygon. My purpose is to create the polygons using lapply() and plot them on the same device.
And actually I have 2 questions : - How can I create some polygons using lapply() with a SpatialPointsDataFrame ? - How can I plot this list of polygons on the same device ? (still using lapply()) Here a little example of I want to do (based on a simple dataframe) : ## Setting a dataframe with coordinates of the centers of the polygons I want to plot : df<-data.frame(Lat=c(3,4),Lon=2,value=0.1) ## Using lists for creating polygons : cc<-list() disc<-list() for (i in 1:nrow(df)) { cc[[i]]<-cbind(df[i,1],df[i,2]) disc[[i]]<-disc(radius=0.1,centre=cc[[i]]) } ## plot the polygons lapply(disc,FUN=plot) This works, but do not plot the polygones on the same device. So I thought about doing this, without success : lapply(disc,function(x) {plot(x,add=TRUE)}) Error in (function (x, y = NULL, density = NULL, angle = 45, border = NULL, : plot.new has not been called yet So, what would you do to simplify this code and make it possible to use the 'add' parameters of the plot() function in a lapply() ? As I am not used to handle apply() functions, I do appreciate your help... Just to let you know, my original idea was to do something like this, considering 'spdf' as a SpatialPointsDataframe : lapply(spdf, function(x) {disc(radius=0.1,centre=coordinates(x))}) Error in as.list.default(X) : no method for coercing this S4 class to a vector Thanks for help -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/using-lapply-with-Spatial-Objects-tp7586911.html Sent from the R-sig-geo mailing list archive at Nabble.com. _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo