| expcov {spatial} | R Documentation |
Spatial covariance functions for use with surf.gls.
expcov(r, d, alpha = 0, se = 1) gaucov(r, d, alpha = 0, se = 1) sphercov(r, d, alpha = 0, se = 1, D = 2)
r |
vector of distances at which to evaluate the covariance |
d |
range parameter |
alpha |
proportion of nugget effect |
se |
standard deviation at distance zero |
D |
dimension of spheres. |
vector of covariance values.
Ripley, B. D. (1981) Spatial Statistics. Wiley.
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.
data(topo, package="MASS") topo.kr <- surf.ls(2, topo) correlogram(topo.kr, 25) d <- seq(0, 7, 0.1) lines(d, expcov(d, 0.7))