R Spatial

1. Load library
    library(rgdal)
    library(maptools)
    library(sp)
2. setwd("directory")  #set default working directory

3.data<-read.table()

4. str(data)

5. coordinates(data) "LAt+Lon"

6. str(data)

7. proje4string(data) = CRS("+init=epsg:4326")

8. spplot()

XX: install rgdal in MacOS.
install.packages('rgdal',repos="http://www.stats.ox.ac.uk/pub/RWin")