rpanel (version 1.1-4)

rp.mururoa: Sampling in Mururoa Atoll

Description

This function is based on a real sampling study on the effects of nuclear experiments conducted between 1966 and 1996 in the South Pacific, at the atolls of Mururoa and Fangataufa, (Report by International Advisory Committee, IAEA, 1998). As part of the assessment of subsequent radiological conditions, both terrestrial and aquatic samples were collected and assayed for activities due to strontium-90, caesium-137, plutonium and tritium. The sampling scenario in the function is based on water sampling by boat in the Mururoa atoll. A graphical control panel allows users to select sampling points. Once the user has drawn a sample, some simple predictions over the whole atoll can be produced.

Usage

rp.mururoa(hscale = NA, col.palette = rev(heat.colors(40)), col.se = "blue", file = NA,
    parameters = NA)

Arguments

hscale

a scaling parameter which expands (>1) or contracts (<1) the size of the plot within the panel. This can be useful for projection onto a screen, for example. The vertical scale is set to the same value as the horizontal scale, to ensure that the plot is square. The default values are 1 on Unix platforms and 1.4 on Windows platforms.

col.palette

the colour palette used to display the predicted and true spatial surfaces.

col.se

the colour used to draw the standard error contours on the predicted surface.

file

the name of a file to which the sampled data will be written.

parameters

a list which can be used to change the parameters which control the simulated measurement data.

Value

Nothing is returned.

Details

The panel controls allow the user to experiment with random and systematic sampling, with further control of the alignment and patterns of points in the systematic case. The number of points can also be selected. When a sample is taken, simulated data are generated. Some further controls allow predicted surfaces and standard errors to be displayed, using different types of trend functions. The geoR package is used to construct these predictions. The true simulated surface can also be displayed, to indicate the success of the predictions.

Once the data have been sampled, a data file may be saved for further analysis external to the rp.mururoa function, using the file argument. A convenient way of saving to the current working directory, for example to a file named mururoa.dmp, is to set the file argument to file.path(getwd(), "mururoa.dmp"). The load function can then be applied to the saved file to create an object called mururoa.data, which is a three-column matrix with the x and y locations in columns 1 and 2 and the observed values in column 3.

References

rpanel: Simple interactive controls for R functions using the tcltk package. Journal of Statistical Software, 17, issue 9.

Bowman, A.W., Gibson, I., Scott, E.M. and Crawford, E. (2008). Interactive Teaching Tools for Spatial Sampling. Journal of Statistical Software, 36, 13, 1--17.

See Also

rp.firth, rp.geosim

Examples

Run this code
# NOT RUN {
  rp.mururoa()
# }

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