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I get the same type of result when there is no file produced at the end of a process. In some cases it is because there is no data because I have input the wrong layers or the layers in the wrong order. In other cases it is because I don't have read / write for all the necessary directories. My installation of QGIS 2.2 has different permissions to my ...


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I just found the answer fo myself, reading the manual carefully and focused. The r.sun mode 2 computes just the clear-sky irridiation. To get the "real-sky" irridiation you have to multiply the result with a clearsky Factor (Kc). Kc is defined as the ratio of messured Irridation on Ground under overcast situation and the clearsky amount messured via ...


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Why don't you crop again with your clipper after vectorizing? That way any combined polygons derived from your raster layer will match your original clipping layer. If you don't want to add an extra step you can vectorize the entire raster layer then clip to vector layer (though this could take more computation time). Any other option I can think of would ...


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The GRASS module v.clean has a tool "rmdangle" to remove short lines that go nowhere. Might help in the first part of your question. This module works on the vectorized layer; you pass it a threshold value to set what the maximum size of a dangle should be.


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To reduce the memory footprint of v.to.rast with large maps, set in v.to.rast the parameter: rows=value to a value much less than the default 4096.


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I highly recommend to use the stable version of Grass (i.e 6.4.4.1). Regards,


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I'm not sure about NVIZ. I would suggest, as an alternative, you look at another QGIS plugin called Qgis2threejs [https://plugins.qgis.org/plugins/Qgis2threejs/]. It can produce higher resolution 3D images than the examples loaded above. See these blogs: http://anitagraser.com/2014/03/15/3d-viz-with-qgis-three-js/ ...


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I think this question has been largely answered except for a couple of points about the issues. Heat maps can be great, but a classic flaw and issue lies with interpretation. Take the difference between a heat map of crime events compared to a map (heat or otherwise) of crime rate/proportion. While the event heat map might be useful in terms of identifying ...


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Perhaps you haven't set computational region correctly? Try running g.region before r.mapcalc: g.region rast=DEM This makes the computational region match the extent of your map DEM. See also: http://grasswiki.osgeo.org/wiki/Computational_region


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GRASS 7 is still in a beta release stage. The Kyngchaos.com package is a stable release of QGIS, which does not yet include GRASS 7 internally. You can get a copy using the Homebrew package manager and the OSGeo4Mac tap: Install Xcode, Xcode Command Line Tools and Homebrew Then, in Terminal run: brew install osgeo/osgeo4mac/grass-70 (if your ...


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To get distances in meters, project the data. How to do that is a mechanical issue readily resolved by referring to the software manuals. The harder part of the question concerns what projection to use? Because a comment to the question indicates that North America is the region of interest, the shape of this continent--and the situation of its coastlines ...


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In spite of what it says in the GRASS manual for v.distance, units are the same as the units of the coordinate system, so in a lat/lon coordinate system you will indeed get decimal degrees. In the GRASS 7 manual the above (incorrect) statement is missing. On the other hand, if you create a Spherical Mercator based LOCATION, EPSG 3857, as you mentioned, the ...


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You want your data projected into Meters, which you can project in GRASS or use QGIS to do that - North_America_Albers_Equal_Area_Conic projection EPSG 102008 would work for North America, for example. Then I'm not sure if you can have data in multiple coordinate systems in 1 workspace, or if you should create a new workspace in EPSG: 102008 to store your ...


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can you help me? I'm trying to modify the plug-in QuickEsport! if possible should be exported to PDF, not only the attribute of the "dbf" the pictures!


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You can call r.mapcalc in for loop. In shell it could look like this: X=5 # initialize first map r.mapcalc "old = 10" # loop for I in `seq $X` do r.mapcalc "new = old + 10" --overwrite g.rename rast=new,old --overwrite done In shell command seq 5 creates a sequence 1, 2, 3, 4 , 5. Note that you shouldn't use r.mapcalc like this (read from and write ...


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It's caused by a picture item with an invalid or corrupt picture path. Click on the item and check the image source.



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