R Notebook

This text is referenced from Introduction to R

• Import avaliable map from raster package

library(raster)

## Warning: package 'raster' was built under R version 3.2.5

## Loading required package: sp

## Warning: package 'sp' was built under R version 3.2.5

map<-shapefile(system.file("external/lux.shp",package = "raster"))

par(mar=rep(2,4))

# assign color to map

n<-length(map)
               
plot(map,border=4,main="Avaliable map",axes=T,col=rainbow(n))

• Check the information of map

# we can add color by randomly sellection

set.seed(123)

n<-sample(length(map))

plot(map,col=rainbow(n),axes=T)

# we can add names to layer

par(mar=rep(2,4))

plot(map,col=rainbow(length(map)),axes=T)

text(map,"NAME_2",cex=0.5)

# Using spplot 

spplot(map,"AREA",main="my map\n 23-6-2017",cex.main=0.02,cex.sub=0.01)

• Read raster in R

library(raster)
b <- brick(system.file("external/rlogo.grd", package="raster"))

# Set resolution and create a raster
r <- raster(map, res=0.01 )

# assign new values to raster

values(r) <- 1:ncell(r)

# clip raster according to region of "map"
r <- mask(r, map)

plot(r)

# add another layer on top

plot(map,add=T)

text(map,"NAME_2",cex=0.5)

image(r,main="my map")

plot(map,add=T, main="my map")

plot(b)

spplot(b,layout=c(3,1))

To be continued