Hello, Here is a late answer, but an answer nonetheless to the question I asked almost one year ago on this list:
> On Wed, 29 Mar 2006, Thibaut Jombart wrote: >> Hello list, <http://tolstoy.newcastle.edu.au/R/help/06/03/24318.html#24322qlink1> />> / />> does anyone know if Monmonier algorithm is available in R? I've checked / />> several spatial libraries, but I didn't find anything related to it. / />> However, there is a huge documentation and I may have missed it. / />> / />> Before coding it, I'd like to be sure it doesn't already exist. / > Googling, I found: > http://www-med-physik.vu-wien.ac.at/staff/rub/abstracts/ISCB_2005.pdf > which is a poster, and refers to using R for boundary finding, and other software for data management and display. >Perhaps the authors are able to help by making code available, the poster looks like a nice example of spatial data >analysis. > -- > Roger Bivand > Economic Geography Section, Department of Economics, Norwegian School of > Economics and Business Administration, Helleveien 30, N-5045 Bergen, > Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 > e-mail: [EMAIL PROTECTED] Basically, Monmonier algorithm aims at finding maximum-difference boundaries between geo-referenced objects. It requires a set of georeferenced objects along with matrix of distances among these objects. Monmonier algorithm is now implemented in the adegenet package (http://pbil.univ-lyon1.fr/software/adegenet/). Main functions are 'monmonier' and 'optimize.monmonier'. Despite the package is devoted to genetic data analysis, these functions can handle other kind of data as well. The main difference I can see between this implementation and the original algorithm is that here, the function uses objects connected on a neighbouring graph rather than polygons of a Voronoi tesselation. Thus, Delaunay triangulation shall be used to recover the original version of the algorithm, but other graphs are also possible (e.g. Gabriel's graph). Regards, Thibaut. -- ###################################### Thibaut JOMBART CNRS UMR 5558 - Laboratoire de Biométrie et Biologie Evolutive Universite Lyon 1 43 bd du 11 novembre 1918 69622 Villeurbanne Cedex Tél. : 04.72.43.29.35 Fax : 04.72.43.13.88 [EMAIL PROTECTED] http://lbbe.univ-lyon1.fr/-Jombart-Thibault-.html?lang=en ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
