surf.ls {spatial} | R Documentation |
Fits a Trend Surface by Least-squares
Description
Fits a trend surface by least-squares.
Usage
surf.ls(np, x, y, z)
Arguments
np |
degree of polynomial surface
|
x |
x coordinates or a data frame with columns x , y , z
|
y |
y coordinates
|
z |
z coordinates. Will supersede x$z
|
Value
list with components
beta |
the coefficients
|
x |
|
y |
|
z |
and others for internal use only.
|
See Also
trmat
, surf.gls
Examples
data(topo)
topo.kr <- surf.ls(2, topo)
trsurf <- trmat(topo.kr, 0, 6.5, 0, 6.5, 50)
contour(trsurf)
points(topo)