orthobasis.poly: Function to compute polynomial of geographical coordinates
In adespatial: Multivariate Multiscale Spatial Analysis

Description Usage Arguments Value Author(s) References See Also Examples

View source: R/orthobasis.poly.R

These functions compute polynomials of geographical coordinates. Polynomials functions are orthogonal and centred for the weights defined in wt (i.e., orthogonal to wt). It is the classical approach to perform trend surface analysis.

1	orthobasis.poly(coords, degree = 2, wt = rep(1/nrow(coords), nrow(coords)))

`coords`	either a `Spatial*` object or a `matrix` with geographic coordinates
`degree`	the degree of the polynomial
`wt`	a vector of weights. It is used to orthogonalize the polynomial functions

an object of class orthobasisSp , subclass orthobasis

St<c3><a9>phane Dray stephane.dray@univ-lyon1.fr

Dray S., P<c3><a9>lissier R., Couteron P., Fortin M.J., Legendre P., Peres-Neto P.R., Bellier E., Bivand R., Blanchet F.G., De Caceres M., Dufour A.B., Heegaard E., Jombart T., Munoz F., Oksanen J., Thioulouse J., Wagner H.H. (2012). Community ecology in the age of multivariate multiscale spatial analysis. Ecological Monographs 82, 257–275.

mem orthobasis

if(require("ade4", quietly = TRUE)){
data(mafragh, package = "ade4")
pol2 <- orthobasis.poly(mafragh$Spatial)

if(require("adegraphics", quietly = TRUE)){
plot(pol2, mafragh$Spatial)
}
}