Generative topographic map, reboot of Ondrej Such's R package
GTM is a cool technique; I like it a little better than SOM in principle.
It's a shame there are none in CRAN, so I figure I'll bring this one up to date and resubmit it.
It is presently broken for 2-d.
Updates of original package:
- renamed the functions to get rid of _'s
- commented out an apparently extraneneous gc()
- added (necessary for R-3.x) NAMESPACE file
- rewrote distance measure for speed (using proxy package)
ToDo: 0) Remove extraneous for loops in gtm.resp6, gtm.trn, add test scripts
- Add some visualizations/OO classes; potential help in: https://github.com/geoss/som_visualization_r http://stackoverflow.com/questions/19858729/r-package-kohonen-how-to-plot-hexagons-instead-of-circles-as-in-matlab-som-too http://nbremer.blogspot.nl/2013/07/on-creation-of-extended-self-organizing.html http://nbremer.blogspot.nl/2013/11/how-to-create-hexagonal-heatmap-in-r.html Also check out hexbin: http://cran.r-project.org/web/packages/hexbin/index.html
- Possible heirarchical representations, aka http://eprints.aston.ac.uk/1314/1/IEEE_Transactions_24_%285%29.pdf
- Temporal extension? http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.129.4734