Hello Nicolas,

thank you for your answer! Reinstalling Osgeo removed the error I mentioned. 
Now I was able to get contour lines (!! When I chose „Auto“ for the advanced 
preference v.out.ogr) with r.contour.step, where I chose the minimum 0 and 
maximum 10 with step size 1. After getting the contour vector layer, I 
transformed it with the tool Vector --> Geometry tools --> from line to polygon 
which gives me areas, that I gave 5 different colors then.
Snapshots of the density raster file and the result (filled contours) are here:
Density: https://postimg.org/image/86yowo0oj/
Filled Contours: https://postimg.org/image/ugk8s349n/

I’m not really satisfied with that result because:

1)      Why is it, that there are white areas where actually there should be 
other than blank? Is it because the contour lines are not closed for these 
areas? I strongly think so - what would be recommended to avoid that ?

2)      When I select „area“ under the advanced preferences in r.contour.step, 
I get NOTHING … not a single value or color… do I have to configure the 
parameters of r.contour.step/level differently?

If you are interested in trying to reproduce that, here is the corresponding 
density .dat raster file. I gave it the style of 5 different colors, 
equidistantly distributed.

Thank you very much for your help, it took me already one step closer tot he 
truth :D

Best regards,

Von: Qgis-user [mailto:qgis-user-boun...@lists.osgeo.org] Im Auftrag von 
Nicolas Cadieux
Gesendet: Donnerstag, 8. September 2016 19:57
An: qgis-user@lists.osgeo.org<mailto:qgis-user@lists.osgeo.org>
Betreff: Re: [Qgis-user] QGIS - help: filled contour lines from raster layer 


I am not sure why you get that error but the r.contour.level will give you what 
you need if you select "area" in the v.out.org<http://v.out.org> parameter.  
That will give you polygons that you can color the fill area. If you have 
installed the latest version of Qgis, your processing toolbox could be a mix of 
old and new tools.  If this is the case, I would do complete reinstall deleting 
all the old plugins.


Envoyé de mon iPad

Le 8 sept. 2016 à 08:47, KOHLMANN Hannes [via OSGeo.org<http://osgeo.org>] 
<[hidden email]</user/SendEmail.jtp?type=node&node=5284798&i=0>> a écrit :
Hello dear QGis users!

A collegue and me were wondering if it is possible to create contour lines, or 
more important for us, FILLED contour lines (areas) for RASTER LAYER data!
We are both very positive that this once worked and we have done that. Now we 
cannot find the way to reproduce that anymore.
On the one hand, we thought that we had done it with the gdal-Contour tool in 
QGIS (Raster->Extract->Contour), but now we can’t find an option to generate 
filled contour areas, like
it is possible with the installable extension „Contour Plugin“ (which is only 
possible to use with a point vector layer, but this is exactly what we think 
that we have done to a raster layer file!).

1.      Now the question: was that ever possible to do with the gdal-contour 
plugin? Or not…

2.      On the other hand, we also tried to use the GRASS Gis algorithms 
r.contour.level or r.contour.step, etc in the processing toolbox, but they keep 
giving us the error message: „environment can only contain strings See log for 
more details“. What ist he problem here? Does it have to do with the new 
version Grass Gis 7?

3.      Bottom line is: We have got a .dat file, which is a raster layer with 
valued pixels that we are displaying in spectral colors. Now we want to extract 
the contour lines and to have a color fill between those contour lines. How 
would you do this – is there an easy solution, which differs from the numerous 
tutorials on the web, which seem to be a lot more complicated than what we 
actually remember to have done?

Thank you very much in advance, any answer would be very helpful!

Best regards,
Hannes Kohlmann

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