point			create an object of class point from a data frame
plot.point		plot the spatial locations, optionally coloring by quantile
identify.point	interactively query a plot of a point object, 
				displaying attribute values
print.point		print descriptive information about an object of class point
pairs			create a pairs structure from an object of class point
print.pairs		print descriptive information about an object of class pairs
lagplot			plot a scatter plot of attribute values at one location versus
				attriubte values at another location, optionally allowing for
				interactive query
spacecloud		plot a variogram cloud plot, optionally allowing for 
				interactive query
spacebox		plot a boxplot of the variogram cloud plot
est.variogram	calculate empirical variogram estimates
plot.variogram  plot empirical variogram estimates, optionally plotting 
				a fitted variogram model
fit.exponential	fit an exponential variogram model to empirical variogram
fit.gaussian	fit an gaussian variogram model to empirical variogram
fit.linear		fit an linear variogram model to empirical variogram
krige			carry out spatial prediction (on points)
