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I'm attempting to create n sub-regions from a polygon based on a cluster analysis of a bunch of overlapping raster layers (physical layers, eg: depth, currents, waves).

Briefly, I can create a regular grid across the polygon, then extract physical attributes from the physical raster layers (eg: Gridspot or equivalent tool) then, run a cluster analysis restricted to n number of clusters (in R or other stats package).

I can then, identify each cluster-group, and plot them back in GIS (QGIS or ArcMap). I envisage however, that some cluster-groups will be dispersed (spatial outliers and not meaningful), whereas some will be clumped (worthy of being a sub-region). I could then manually draw around representative clumps to create n sub-regions.

Is there a tool like ArcMap 10.1 Grouping Analysis that can be run in QGIS? I'm only running 10.0.

Are there suggestions of a better way to do cluster analysis of multiple raster layers, to create n sub-regions (bio-regions)?

share|improve this question
Not sure I'm understanding the role of the polygon. If you only have a single polygon, perhaps you can just clip the rasters as a pre-process and then run your cluster analysis directly on the rasters? Presuming you'll create a multi-dimensional raster/array as input, you should get an set of cluster ids back, you can visualize this (either by displaying the raster directly or converting back to a vector representation). – Roland Sep 16 '13 at 21:07
Maybe take a look at clusterPy? – Joseph Jan 14 at 11:01
@Joseph I have only put the bounty on this to try to help out… so if you think clusterPy will help then be sure to add an answer. – PolyGeo Jan 18 at 8:22
@PolyGeo - clusterPy may help with this post as it mainly analyses clusters in rasters. But I haven't used it myself so not sure if it will help with only clustering points. – Joseph Jan 18 at 12:59

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