Rapid statistics for subareas of a raster map?

[Harini Nagendra]

Hi,

Some additional info. http://sevilleta.unm.edu/~bmilne/le.soft.txt has a
lot of details on several different software packages available to
calculate several kinds of landscape and patch statistics. I just found
it, and it looks pretty comprehensive.....

Harini Nagendra

On 21 Aug 1998 hnw at mtqgrass.ESD.ORNL.GOV wrote:

> I need to calculate n, mean, std, max, and min for a number of patches
> in a raster map.
> 
> I am currently masking the patch, zooming with g.region, and then using
> r.stats to spew the cells to an awk program which calculates the
> statistics.
> 
> But it takes a long time for g.region to "walk" the edges of the window
> down to each individual patch.  But if I don't window in the current
> region, it takes r.stats a long time to filter through all of the
> masked cells to get to the cells that are in the current patch.
> 
> Does anybody know of a better, faster approach for getting summary
> stats for patches in a raster map?
> 
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