I am facing a problem with GrassGis 7.0.1. I want to install r.viewshed.cva form Addons. I don't get an error during installation but when I try to open the plugin I get the error :

Unable to fetch interface description for command

Can anyone help me? I am on windows

  • How to you install it, and on which operating system? – markusN Oct 24 '15 at 11:45
  • Ah, your error message shows that you requested "r.vieshed.cva" - but the name is "r.viewshed.cva". Maybe just a typo? – markusN Oct 24 '15 at 11:45
  • Oh I wrote it wrong here (sorry!), but I wrote it right in grass command console. I am on windows 7. – geo_dd Oct 24 '15 at 12:49
  • 1
    ok I took liberty to edit your posting for that typo. - concerning Windows I have no idea since I'm on Linux where installation with "g.extension r.viewshed.cva" works fine (it is "just" a Python script). - You could just download it from here: svn.osgeo.org/grass/grass-addons/grass7/raster/r.viewshed.cva and use it. – markusN Oct 25 '15 at 0:05

I have probably found the error and updated the command in the GRASS GIS Addons repository. Within 24 hours (i.e. tomorrow), the updated module will be online available:

g.extension r.viewshed.cva


Thank you markusN for your interest! It worked. Because of the problem with the plugin, I did the viewshed analysis through command shell. First I saved my points in ascii with the command:

v.out.ascii --overwrite input=points@vis type=point output=C:\coordinatess format=point separator=space precision=4

With this I created a .txt file with three columns i,j,k(x_coordinates,y_coordinates,points_id)

Then I used the r.viewshed plugin for one point and kept the command:

r.viewshed -c -b input=dem@vis output=point1 coordinates="x1", "y1"  observer_elevation="value" max_distance="distance"

Finally I wrote the 'For' command in one row and run it in command shell for 1000 points :

FOR /F "tokens=1,2,3" %i in (coordinates.txt) do r.viewshed -c -b input=dem@vis output=point%k coordinates=%i,%j observer_elevation="value" max_distance="distance"

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