Ftransdraw {EnviroStat} | R Documentation |
An interactive function showing the fitted variogram and the mapping transformation from the geographical space into D-space, allowing the user to interactively choose a suitable value for the smoothing parameter ("lambda").
Ftransdraw(disp, Gcrds, MDScrds, gridstr, sta.names, lambda = 0, lsq = FALSE, eye, model = 1, a0 = 0.1, t0 = 0.5)
disp |
n \times n dispersion matrix, equal to 2-2 (spatial correlation matrix) |
Gcrds |
n \ times 2 coordinate matrix (in G-space) |
MDScrds |
Coordinates of new locations – as calculated by
|
gridstr |
grid coordinates, obtained from |
sta.names |
names of locations; if not provided, locations will be numbered 1 to n |
lambda |
initial value of the smoothing parameter |
lsq |
logical flag used in Sampson-Guttorp method |
eye |
eye perspective; if not provided, locations will be selected using the provided data |
model |
type of variogram: 1 for exponential or 2 for gaussian |
a0, t0 |
initial variogram parameter estimates |
A list containing the following named components:
Dcrds |
n \times 2 cooridnate matrix of new locations in D-space |
Ddist |
n \times n matrix of interdistances in D-space |
The graphic device has to be setup before engaging this function, for example using the 'setplot' function:
par(mfrow=c(1,2)) temp <- setplot(coords.lamb, ax=TRUE)
In window, after entering the function call in R console, click on the graphical device to register the curse before proceeding and this interactive function will provide instructions for using a different smoothing parameter value; ie. enter a new lambda value in R console, then click on the graphical device to see results.