[GRASS-user] import satellite data in Grass
hamish_b at yahoo.com
Fri Jun 20 09:06:55 EDT 2008
> What I want to do now, is to overlay the images with a raster and
> define (in a first time at least by hand) a value for each of the
> the raster cells. Is there anything foreseen in Grass that could
> help me with this? Or do I have just to write a table in any other
could you please expand a little bit more? I have trouble understanding exactly the process you wish to do.. r.coin? r.patch? r.mapcalc?
'd.rast -o' + d.what.rast?
> What I also want to do, is measure distances and angles between
> objects on my images. For the moment I don't really see where
> to search for this kind of tools. I thought that it would be possible
> to draw lines and measure them and angles between them?
m.cogo might help. or 'v.distance upload=to_along,to_angle', d.measure, v.to.db...
In general beware to double check results/meaning if using a lat/lon location (see d.rhumbline and d.geodesic), or map projection with possibly heavy distortion at far distances.
If you build the Python SWIG interface there is also a m.distance module to look at.
see also this thread+code patch from March:
"How to find out an angle between to points on the map"
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