###################################################
# NOTE: requires the prior installation of the
# maps package from CRAN and online access
# to Sourceforge
if (!require(spmaps)) {
  rSpatial <- "http://r-spatial.sourceforge.net/R"
  install.packages("spmaps", repos=rSpatial)
  library(spmaps)
}
ill <- map("county", regions="illinois", plot=FALSE, fill=TRUE)
IDs <- sub("^illinois,", "", ill$names)
ill_sp <- map2SpatialPolygons(ill, IDs, CRS("+proj=longlat"))
plot(ill_sp, axes=TRUE)


###################################################
IJ.east <- 4.516666667
IJ.north <- 52.46666667
WGS84 <- CRS("+proj=longlat +datum=WGS84")
IJ.WGS84 <- SpatialPoints(cbind(x=IJ.east, y=IJ.north), WGS84)
library(rgdal)
EPSG <- make_EPSG()
EPSG[grep("^# ED50$", EPSG$note), 1:2]
ED50 <- CRS(paste("+init=epsg:4230", "+towgs84=-87,-98,-121,0,0,0,0"))
res <- spTransform(IJ.WGS84, ED50)
coordinates(res)
spDistsN1(coordinates(res), coordinates(IJ.WGS84), longlat=TRUE)


###################################################
EPSG[grep("Amersfoort", EPSG$note), 1:2]
RD_New <- CRS("+init=epsg:28992")
res <- CRSargs(RD_New)
res
showWKT(CRSargs(RD_New), morphToESRI = TRUE)


###################################################
# NOTE: please unpack unitB_data.zip in the
# working directory before trying to read
# the shapefile
library(maptools)
list.files("shapes")
getinfo.shape("shapes/scot_BNG.shp")
scot <- readShapePoly("shapes/scot_BNG.shp")


###################################################
ogrDrivers()
scot1 <- readOGR(dsn="shapes", layer="scot_BNG")
proj4string(scot1)


###################################################
getGDALDriverNames()
list.files("pix")
SP27GTIF <- readGDAL("pix/SP27GTIF.TIF")


###################################################
image(SP27GTIF, col=grey(1:99/100), axes=TRUE)


###################################################
summary(SP27GTIF)