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Compute Spatial Correlograms
Usage
correlogram(krig, nint, plotit=T, ...)
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
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 = T
.
See Also
variogram
, expcov
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))