Last data update: 2014.03.03

R: Plot section views of a kriging model, including design...
sectionview.kmR Documentation

Plot section views of a kriging model, including design points

Description

Plot one section view per dimension of a kriging model thus providing a better understanding of the model behaviour including uncertainty.

Usage

  sectionview.km(model, type = "UK", center = NULL,
    axis = NULL, npoints = 100, col_points = "red",
    col_surf = "blue",
    conf_lev = c(0.5, 0.8, 0.9, 0.95, 0.99),
    conf_blend = NULL, bg_blend = 5, mfrow = NULL,
    Xname = NULL, yname = NULL, Xscale = 1, yscale = 1,
    xlim = NULL, ylim = NULL, title = NULL, add = FALSE,
    ...)

Arguments

model

an object of class "km".

type

the kriging type to use for model prediction.

center

optional coordinates (as a list or data frame) of the center of the section view if the model's dimension is > 1.

axis

optional matrix of 1-axis combinations to plot, one by row. The value NULL leads to all possible combinations i.e. 1:D.

npoints

an optional number of points to discretize plot of response surface and uncertainties.

col_points

color of points.

col_surf

color for the section.

conf_lev

an optional list of confidence interval values to display.

conf_blend

an optional factor of alpha (color channel) blending used to plot confidence intervals.

bg_blend

an optional factor of alpha (color channel) blending used to plot design points outside from this section.

mfrow

an optional list to force par(mfrow = ...) call. The default value NULL is automatically set for compact view.

xlim

an optional list to force x range for all plots. The default value NULL is automatically set to include all design points.

ylim

an optional list to force y range for all plots. The default value NULL is automatically set to include all design points (and their 1-99 percentiles).

Xname

an optional list of string to overload names for X.

yname

an optional string to overload name for y.

Xscale

an optional factor to scale X.

yscale

an optional factor to scale y.

title

an optional overload of main title.

add

to print graphics on an existing window.

...

further arguments passed to the first call of plot.

Details

A multiple rows/columns plot is produced. Experimental points are plotted with fading colors. Points that fall in the specified section (if any) have the color specified col_points while points far away from the center have shaded versions of the same color. The amount of fading is determined using the Euclidean distance between the plotted point and center.

Author(s)

Yann Richet, IRSN

See Also

The function sectionview3d.km produces a 3D version. For more information on the km class, see the km function in the DiceKriging package.

Examples

## A 2D example - Branin-Hoo function
## a 16-points factorial design, and the corresponding response
d <- 2; n <- 16
design.fact <- expand.grid(seq(0, 1, length = 4), seq(0, 1, length = 4))
design.fact <- data.frame(design.fact); names(design.fact)<-c("x1", "x2")
y <- branin(design.fact)

## kriging model 1 : matern5_2 covariance structure, no trend, no nugget effect
m1 <- km(design = design.fact, response = y)

sectionview(m1, center = c(.333, .333))

## Display reference function
sectionview(branin,dim=2,center=c(.333, .333),add=TRUE,col='red')

Results


R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(DiceView)
Loading required package: DiceKriging
Loading required package: DiceEval
Loading required package: rgl
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/DiceView/sectionview.km.Rd_%03d_medium.png", width=480, height=480)
> ### Name: sectionview.km
> ### Title: Plot section views of a kriging model, including design points
> ### Aliases: sectionview.km
> ### Keywords: models
> 
> ### ** Examples
> 
> ## A 2D example - Branin-Hoo function
> ## a 16-points factorial design, and the corresponding response
> d <- 2; n <- 16
> design.fact <- expand.grid(seq(0, 1, length = 4), seq(0, 1, length = 4))
> design.fact <- data.frame(design.fact); names(design.fact)<-c("x1", "x2")
> y <- branin(design.fact)
> 
> ## kriging model 1 : matern5_2 covariance structure, no trend, no nugget effect
> m1 <- km(design = design.fact, response = y)

optimisation start
------------------
* estimation method   : MLE 
* optimisation method : BFGS 
* analytical gradient : used
* trend model : ~1
* covariance model : 
  - type :  matern5_2 
  - nugget : NO
  - parameters lower bounds :  1e-10 1e-10 
  - parameters upper bounds :  2 2 
  - best initial criterion value(s) :  -81.3824 

N = 2, M = 5 machine precision = 2.22045e-16
At X0, 0 variables are exactly at the bounds
At iterate     0  f=       81.382  |proj g|=       1.0001
At iterate     1  f =       81.293  |proj g|=        0.9569
At iterate     2  f =       81.085  |proj g|=         0.974
At iterate     3  f =       81.059  |proj g|=       0.16292
At iterate     4  f =       81.058  |proj g|=      0.016096
At iterate     5  f =       81.058  |proj g|=    0.00030849
At iterate     6  f =       81.058  |proj g|=     5.687e-07

iterations 6
function evaluations 8
segments explored during Cauchy searches 8
BFGS updates skipped 0
active bounds at final generalized Cauchy point 1
norm of the final projected gradient 5.68701e-07
final function value 81.0576

F = 81.0576
final  value 81.057643 
converged
> 
> sectionview(m1, center = c(.333, .333))
> 
> ## Display reference function
> sectionview(branin,dim=2,center=c(.333, .333),add=TRUE,col='red')
[1] 0 1
[1] 0 1
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>