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4

I recommend you to use the brand new geoalgorithm from QGIS 2.14.1, named Smooth.py With Smooth Geometry it's possible to smooth the entire polygon, not only the boundaries, as in Chaiken method from v.generalize


4

Make sure the file is either txt file or csv file. Go to Qgis click "Layer->add layer->add delimited text layer". Browse to the file. In the window that opens check if the X Y Z values are in correct column. Else you need to to change the delimiter in same window. Once your set click OK. In coordinate reference system selector you browse to the correct ...


3

Yes, it is possible to launch the GRASS GUI from R within a running GRASS session. It did not work because the environment variables where not correctly set. Modifiying the environment variables as follows solved the problem: # Set PYTHONPATH Sys.setenv(PYTHONPATH = ...


3

Did you check GRASS r.lake function: https://grass.osgeo.org/grass70/manuals/r.lake.html


3

http://qgis.org/debian/dists/trusty/main/binary-i386/Packages only contains packages for grass6, while http://qgis.org/ubuntugis/dists/trusty/main/binary-i386/Packages supports grass7 only. You might have to compile QGIS from source, or remove the debian packages from your Linux, and switch to the ubuntugis ones. While this works for trusty (and Linux Mint ...


2

If you have a Digital Elevation Model, you could calculate the distance travelled downhill (actual distance along flow paths, not the distance in a straight line) by a drop of water from a point of origin to a point of interest (let's say a raster cell). This is called the slope length and is used in modelling soil erosion. The r.watershed module can ...


2

The tool you are looking for is the SAGA tool Accumulated Cost (isotropic). To calculate the accumulated costs, you will need a "destination" point and the cost raster as input. Note that the destination point is needed as a raster cell, so you need to convert shape points (using e.g. the GDAL rasterize tool). From there on, if you want, you can use the ...


1

If run grass7.0.3 standalone nviz module works, and in grass7.0.3/bin there isn't nviz and/or nviz7 binary file!? Seems that nviz7 command is moved in the ./qgis/python/plugins/processing/algs/grass7/nviz7.py.


1

When you execute an algorithm in the Processing Toolbox, the result is recorded in the file /.../.qgis2/processing/processing.log With the command Nviz7, the result in the processing.log file is processing.runalg("grass70:nviz7","/path_to/dem.tif",None,None,"202086.577,205625.414407,88411.048,90534.3504441",0) The Python processing module of QGIS uses ...


1

The issue is that you are using: r.region map=dem n=32:13:51N s=32:13:34N e=110:56:46W w=110:57:13W and the correct format is: r.region map=dem n=32:13:51N s=32:13:34S e=110:56:46E w=110:57:13W In my particular case, I tried out with: r.region map=palma.blue n=09:30:00N s=09:27:00S w=84:07:30W e=84:07:01E and it works perfectly; as it can be ...


1

Use the join functionality in QGIS. A precondition to do this is that you have shared keys (name/code) across the layers you are joining. Add your external excel-file by dragging and dropping it in the layer overview. Open layer properties for your spatial layer by right-clicking and select the join. Select join over the shared columns - in your case ...


1

Various r.stream.* modules must be installed as addons with g.extension. This must be done in GRASS explicitly, because g.extension seems not available via QGIS. see for details: https://grasswiki.osgeo.org/wiki/AddOns/GRASS7/raster This works fine for GRASS7 as a standalone application. edit/add: ... but might not really solve your issue, but this might ...


1

As pointed by @wenzeslaus this question was asked on grass-user mailing list and it was answered. According to Martin Landa, it happened that on 64 bit installations the liblas_c.dll file was not available. Then, the build environment was updated and the OP there confirmed the problem was solved. A re-package of GRASS 7.0.3 to include liblas for 64 bit ...


1

It is meant only for USLE computations. You don't specify output length_slope, so max_slope_length does not influence anything.


1

I had this exact same problem with a small dataset (16 mil. points out of which GRASS was labeling as invalid about 30%). Luckily I also had another dataset that imported fine in GRASS so I compared them, and as wenzeslaus suggested, the only notable difference was that the second dataset had no scan angle information stored (i.e. all values were 0). This ...


1

I have done all modules of grass7.0.3 works but nviz7 NO! Could be a PATH problems. The nviz7 command isn't under grass7.0.3 dir!? I found nvzi7.py in the ./qgis/python/plugins/processing/algs/grass7/nviz7.py dir but how could by call!?



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