[GRASS-user] Converting vector points to areas?

[Hamish]

Justin wrote:
> Hello,  I’m working with LiDAR data imported as vector points. Ideally
> we would like to consolidate groups of close-together points into
> vector areas. Is there a way to do this automatically, maybe based on
> proximity? We’ve looked into using v.delaunay, but this seems to
> combine ALL points into a single area. We only want points in close
> proximity to be combined into areas.  Any help you can give is greatly
> appreciated!

v.buffer is one way.. for LIDAR coverage extent maps I'd usually try a
2-5m buffer around all points. If that's too slow for a massive dataset
then v.to.rast+r.buffer or r.in.xyz+r.buffer may help.

perhaps you want something like v.kernel + a threshold extraction?

or perhaps a good thing to look at is one of the "home range" add-on
modules (which is essentially a similar thing) maybe Anne could comment
on that?
 http://grass.osgeo.org/wiki/GRASS_AddOns#v.adehabitat.clusthr.2C_v.adehabitat.kernelUD.2C_v.adehabitat.mcp

or v.points.cog + v.buffer
 http://grass.osgeo.org/wiki/GRASS_AddOns#v.points.cog

or something with v.hull? (but that's all points..)

or as raster points with one of the 'clump' algorithms?

and if all else fails, the R-stats interface will surely have some tool..


Hamish