> Depends on your GIS! Shapefiles only have a 1-1 relationship, but > that's because they are a bit rubbish. If you use a proper spatial > database then you can do one-many. This is an application for a > PostGIS or Spatialite database, and if your GIS can read that (Qgis > for example) then you are sorted.
I want to do it in R. R can do quick and pretty graphs and maps! >> The result data I am trying to map using spplot has 1 to 70 years >> periods. I want to produce maps per period, for 10 years or more for >> forest management regimes in forest stand. > > I wouldn't reshape the data in R to create a possibly sparse matrix, > and then have to code in column names with expressions (e.g. > data[,paste("Year",y,sep="")], which I think is icky). I would just > create a spatial polygons/points data set with just an ID column, and > put your ID/Period/Age data in a non-spatial data frame. Then when you > want to plot a particular thing, just match up the data with the > spatial data and plot (using the 'match' function). This is what actually I wanted! "column names with expressions (e.g. data[,paste("Year",y,sep="")]" in shapefile database? Yes, created Crop_ID which is supposed to be Polygon ID in my foreststand.dbf. I have also Crop_ID, Period, Age in non spatial table i.e. harvest.dbf This is the harvest.dbf names(harvest.dat) = c("CROP_ID", "CROPTYPE", "Period","Ini_Age","Cut_Age", "Area_Cut") Barry, any snippet how to use match in spplot or plot. Thanks. Noli _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo