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I'm having some trouble plotting a RasterLayer and a SpatialPolygonsDataFrame in a level plot in R. Something is wrong with the projection, but I don't understand what.
Here you can find my reproducible example data and code:
library(sp)
library(rgdal)
library(rgeos)
library(raster)
library(rasterVis)
library(maptools)
setwd("C:/...path_to/test2")
data<-read.csv("test.csv", header=TRUE)
#creating the raster from a data.frame and giving projection
raster<-rasterFromXYZ(data, crs="+proj=longlat")
raster_proj<-projectRaster(raster, crs="+proj=longlat +datum=WGS84
+ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs")
#loading shapes
nuts<-readShapePoly("NUTS_RG_WGS84.shp", proj4string=CRS("+proj=longlat"))
countries<-readShapePoly("countries.shp", proj4string=CRS("+proj=longlat"))
#subsetting the raster
raster_clip<- crop(raster_proj, countries, snap="near")
#plot
p.strip <- list(cex=1.5, lines=1, fontface='bold')
x.scale <- list(cex=1.5)
y.scale <- list(cex=1.5)
label <- list(labels=list(width=1, cex=1.5), height=0.95)
levelplot(raster_clip, par.settings = RdBuTheme, margin=FALSE,
at=seq(min(na.omit(values(raster_clip))), max(na.omit(values(raster_clip))), length.out=15),scales=list(x=x.scale, y=y.scale),
par.strip.text=p.strip, colorkey=label, xlab=list(label="Longitude", cex=2), ylab=list(label="Latitude", cex=2))+
layer(sp.polygons(nuts))+layer(sp.polygons(countries))
The error message is:
Error: Attempted to create layer with no geom.
But the raster and the polygons are in the same projection. I also tried to re-project the polygons using:
nuts <- spTransform(nuts, CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs"))
countries <- spTransform(countries, CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs"))
Any Idea?
