fit_trend_surface: Fits a trend surface by least-squares to a RasterLayer.

In GastonMauroDiaz/rdemtools: Digital elevation model editing tools

Description

Fits a trend surface by least-squares to a RasterLayer.

Usage

fit_trend_surface(x, size = ncell(x), np = 3)

Arguments

x	RasterObject.
size	positive integer giving the number of items to choose
np	degree of polynomial surface
sampleProportion	numeric. Fraction. Approximate proportion of pixels that will be passed on to surf.ls as xyz coordinates. sampleRandom is used with the argument size as ncell(x) * sampleProportion.

Details

Fits a trend surface by least-squares to an object of class RasterLayer. This function is powered by surf.ls.

Value

RasterObject.

Examples

r <- raster()
r[] <- seq(1, ncell(r)) + rnorm(ncell(r), 20000, 10000)
plot(r)
s <- fit_trend_surface(r, np = 1)
plot(s)
par(mfrow = c(1,2))
plot(r, legend = FALSE)
plot(r - s, legend = FALSE)

GastonMauroDiaz/rdemtools documentation built on Oct. 22, 2019, 8:32 p.m.