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rdictionarycartography

Plot points map of population

I want to plot kind of isarhytmoc points map like in this tutorial, but with population data. However, unfortunately, I have no enough skill and only came with such code:

require(sp)
require(rgdal)
require(RColorBrewer)
require(ggplot2)
library(plyr)
library(maptools)
library(rgeos)
require(gpclib)
gpclibPermitStatus() 
gpclibPermit()


rus<-url("http://www.filefactory.com/file/4h1hb5c1cw7r/n/RUS_adm1_RData")
print(load(rus))
proj4.str <- CRS("+init=epsg:3413 +lon_0=105")
gadm.prj <- spTransform(gadm, proj4.str)


popul <- read.csv2(file="C:\\unempl11.txt", header = TRUE, 
        sep = ";",quote = "", dec=",", stringsAsFactors=F)

df <- fortify(gadm.prj, region = "ID_1")
df2 <- merge(df, gadm.prj, by.x="id", by.y="ID_1")






p <- ggplot(df2, aes(x = long, y = lat, group=group)) +
       geom_point(data    = popul,  
                  mapping = aes(x=lon, y=lat, colour=abs),
                  size    = 3,
                  alpha   = 0.8) +
       scale_colour_gradient2(name  = "Population",
                              low   = "darkred",
                              mid   = "white",
                              high  = "blue",
                              guide = "colorbar") +
       ggtitle("Population in Russia)")
p + geom_path(data    = df2,
               mapping = aes(x=long, y=lat, group=group),
              size    = 0.125)

Here is the data I use, if anyone can help me with some ideas i will be grateful.

Solution

  • You are trying to display points but you are using an SpatialPolygonsDataFrame source. You can extract the coordinates of the centroids with coordinates and use them as coordinates of your data, but I am not sure if that is what you need:

    library(sp)
library(rgdal)

rus <- url("http://www.filefactory.com/file/4h1hb5c1cw7r/n/RUS_adm1_RData")
load(rus)
proj4.str <- CRS("+init=epsg:3413 +lon_0=105")
gadm.prj <- spTransform(gadm, proj4.str)
## IDs needed to match polygons and data
nms <- gadm.prj$NAME_1

ll <- coordinates(gadm.prj)

    On the other hand, I cannot retrieve correctly the data column of your file. I fill it with some noise:

    popul <- read.csv2('/tmp/popul.txt')
popul$data <- runif(nrow(popul))

    Now it's time to match coordinates and data (similar to what we did in this previous question):

    ord1 <- match(nms, popul$region)
popul <- popul[ord1,]
row.names(popul) <- nms
row.names(ll) <- nms

popSP <- SpatialPointsDataFrame(ll, popul["data"], proj4string=proj4.str)

    This SpatialPointsDataFrame can be directly displayed with spplot with the boundaries below using sp.layout.

    spplot(popSP, sp.layout=list('sp.polygons', gadm.prj))

    result