[GRASS-user] Local Relief Model tool

[Vaclav Petras]

To answer Hamish's questions, here are some images (DEM+LRMs) of a smaller
region in nc_spm. The idea is really to remove the overall main terrain
features while small local differences are preserved.

For getting of the smooth terrain, random points and v.surf.rst or
v.surf.bspline are probably good alternative. I had no chance to test
various alternatives yet. I just tried smoothing + contours + r.fillnulls
module and it worked so I staid with it.

The contours related (contour->dem) modules cannot be used since the
contours are actually not contours of the elevation but of the first
approximation of LRM. Than the values of elevation are assigned to the
points/cells of contours.

As for the script installation, it would be nice to have direct
installation form github.com, but this is really a grass-dev topic.

Vaclav


On Thu, Sep 26, 2013 at 2:48 AM, Hamish <hamish_b at yahoo.com> wrote:

> Eric:
> > To install in a linux environment, I followed the instructions at
> >
> http://grasswiki.osgeo.org/wiki/GRASS_and_Python#Testing_and_installing_Python_extensions
> .
> >
> > I haven't been able to find solid information on how users who don't
> > compile themselves can install an addon that isn't available via
> > g.extension.
>
> In general it's quite simple, users maintain a directory with all of
> their executable scripts in it and before starting GRASS add
> export GRASS_ADDON_PATH=/path/to/files
> to their ~/.bashrc. (~/.grass.bashrc is no good, the variable has to
> be set before grass starts)
>
> Then it magically finds them. The g.extension module(s) just fits itself
> into that and creates you an addon dir if one wasn't already set.
> For scripts there is no other install or compiling needed, just put
> it in a dir somewhere which is in the $PATH.
>
> Python might be a problem, but if you just call your module by its full
> name it should be ok (so with or without .py, just be sure to match
> the exact filename).
>
>
> > There is
> > http://grasswiki.osgeo.org/wiki/Compile_and_Install#Scripts, but I'm
> > not sure how that applies to Windows users. Any advice in this area
> > would be much appreciated.
>
> The GRASS 6 make system is still missing build support for python
> scripts (often it tries to reuse the shell Script.make, which mostly
> works on Linux). Smooth building with correct .bat file wrappers
> on Windows remains an issue. It can be done, I've seen it work, but
> still needs a new PythonScript.make to work smoothly. (similarly user-
> created personal shell scripts for GRASS 7 should have a ShellScript.make
> to help folks who need that, even if there are none in the main release.)
>
>
> regards,
> Hamish
>
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> grass-user at lists.osgeo.org
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>
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