# Ftransdraw: Interactively choose smoothing parameter value In EnviroStat: Statistical Analysis of Environmental Space-Time Processes

## Description

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").

## Usage

 1 2 Ftransdraw(disp, Gcrds, MDScrds, gridstr, sta.names, lambda = 0, lsq = FALSE, eye, model = 1, a0 = 0.1, t0 = 0.5) 

## Arguments

 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 Falternate3 gridstr grid coordinates, obtained from Fmgrid using Gcrds as input 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

## Value

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

## Note

The graphic device has to be setup before engaging this function, for example using the 'setplot' function:

 1 2 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.

EnviroStat documentation built on May 30, 2017, 5:38 a.m.