## ----raster-119---------------------------------------------------------------
library(raster)
rasterOptions()


## ----raster-120---------------------------------------------------------------
r1 <- raster(ncol=36, nrow=18)
r2 <- r1
values(r1) <- runif(ncell(r1))
values(r2) <- runif(ncell(r1))
s <- stack(r1, r2)
sgdf <- as(s, 'SpatialGridDataFrame')
newr2 <- raster(sgdf, 2)
news <- stack(sgdf)


## ----raster-132---------------------------------------------------------------
setClass ('myRaster',
	contains = 'RasterLayer',
	representation (
		important = 'data.frame',
		essential = 'character'
	) ,
	prototype (
		important = data.frame(),
		essential = ''
	)
)
	
r <- raster(nrow=10, ncol=10)

m <- as(r, 'myRaster')

m@important <- data.frame(id=1:10, value=runif(10))
m@essential <- 'my own slot'
values(m) <- 1:ncell(m)



## ----raster-133---------------------------------------------------------------
setMethod ('show' , 'myRaster', 
	function(object) {
		callNextMethod(object) # call show(RasterLayer)
		cat('essential:', object@essential, '\n')
		cat('important information:\n')
		print( object@important)
	})	
	
m