[GRASS-dev] library of data partitioning algorithms
Roger.Bivand at nhh.no
Mon Nov 27 10:18:05 EST 2006
On Mon, 27 Nov 2006, Moritz Lennert wrote:
> In the effort of creating a C-version of d.vect.thematic we are planning
> on using a series of library functions for data partitioning which would
> contain classical algorithms such as equal interval, quantiles, stdev,
> etc, but also more sophisticated ones such as "natural breaks" or
> kmeans. They would take a vector of data and the number of desired
> classes and return the breakpoints.
> These functions could then be used by other modules, such as d.vect.chart.
> I have two questions concerning this:
> 1) Where should we integrate these functions ? lib/stats is currently
> limited to raster, should we integrate non-raster functionality in there ?
> 2) Does anyone know of an existing C-library of such functions. Just so
> that we don't reinvent the wheel.
You'll find some references in the R classInt package on CRAN, including
the Fortran for Fisher-Jenks (not C). There is a good deal of C code in R
itself, some from statlib.
> grass-dev mailing list
> grass-dev at grass.itc.it
Economic Geography Section, Department of Economics, Norwegian School of
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e-mail: Roger.Bivand at nhh.no
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