Compute Spatial Correlograms
Usage
correlogram(krig, nint, plotit=TRUE, ...)
Arguments
krig
|
trend-surface or kriging object with columns x , y , and z
|
nint
|
number of bins used
|
plotit
|
logical for plotting
|
...
|
parameters for the plot
|
Description
Compute spatial correlograms of spatial data or residuals.Details
Divides range of data into nint
bins, and computes the covariance for
pairs with separation in each bin, then divides by the variance.
Returns results for bins with 6 or more pairs.Value
x
and y
coordinates of the correlogram, and cnt
, the number of pairs
averaged per bin.Side Effects
Plots the correlogram if plotit = TRUE
.See Also
variogram
Examples
data(topo)
topo.kr <- surf.ls(2, topo)
correlogram(topo.kr, 25)
d <- seq(0, 7, 0.1)
lines(d, expcov(d, 0.7))