Message: 3
Date: Mon, 22 Nov 2010 09:53:57 +0000
From: Roy Sanderson<r.a.sanderson@newcastle.ac.uk>
Subject: [GRASS-user] Points buffering without dissolve query
To:grass-user@lists.osgeo.org
Message-ID:<4CEA3DB5.8010902@newcastle.ac.uk>
Content-Type: text/plain; charset=ISO-8859-1; format=flowedDear All
I have someone with a GRASS map of several thousand points which we wish
to buffer around each point 1km, but without dissolving buffer circles
into each other (some points are less than 1 km apart). Then we plan to
overlay the buffers onto a raster map, and extract the raster cell
composition information within each buffer into a separate file
(rows-sites; columns-raster categories within each buffer).
Unfortunately, this should ideally work on a Windows version of GRASS
(end-user request), although as I use Linux this may still provide a
solution otherwise.I would be grateful for any advice on the appropriate method (GRASS 6.4)
Many thanks
Roy
Roy,
When v.buffer was re-written, someone removed the "debug=buffer" option which would have given you exactly what you wanted.
However, if you are on Linux, there is a solution. Go to the source of an older version, even one of the early 6.4 release candidates, and get the source code of v.buffer.
You can give it a new name - I use v.oldbuffer - and compile it as this.
You can then run it as v.oldbuffer and use debug=buffer to get the "undissolved" output. I use this quite frequently when I have a very large number of overlapping buffers, because Grass can stall when it's trying to clean the output.
Richard