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I have found Dos3 to be more relistic for Landsat 5 on the plains for green crops. No experience in other situations. Landsat 8 will respond differently to the various correction methods, compared to L5. I haven't used GRASS in a while, have migrated to the plugin for QGIS - see http://fromgistors.blogspot.com/


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For the record, the question was answered in the GRASS User list: http://lists.osgeo.org/pipermail/grass-user/2014-December/071451.html


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I resolved this going to directory that has the module: cd /home/(personal)/grass-7.0.svn/raster/r.stream.order as root, I type: make MODULE_TOPDIR=/home/(myhome)/grass-7.0.svn/ make MODULE_TOPDIR=/home/(myhome)/grass-7.0.svn/ install More information you can find here.


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I would like to reply myself after a while. This is caused because the weigth of the layers it's too high, and the Pandolf's formula used it's very sensitive to this. Lowering the weight was the solution to my problems. This is a formula used commonly in archaeology.


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I think you will have to use something like v.build.polyline. Edit: From the man page: v.build.polyline picks a line and from its start node, walks back as long as exactly one other line of the same type is connected to this node. ...[polylines] sometimes [are] broken into their constituent straight line segments during conversion from one data ...


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Still in QGIS 2.4 there are no focal statistics, i.e. filters, per se, and I do not think that there will be any in the future. However, SAGA can be reached via the Processing tool box. In the SAGA command list you can choose Grid - Filter and then you have plent of a choice. I suggest using the "user defined filter" if you know what you are doing or the ...


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i.landsat.toar derives, by default, Spectral Reflectance values (unitless, ranging in [0,1]), whether uncorrected or corrected (by some of the possible DOS methods). i.atcorr treats, by default, input bands as Spectral Radiance. To make things work, either derive Spectral Radiance values via i.landsat.toar by instructing the -r flag, or let i.atcorr treat ...


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The way I have done this in the past is to convert buildings, forested areas, etc. to a raster (rasterize the polygon using the height column for the raster value, using the same pixel resolution as the DEM). Then merge the two rasters (DEM and rasterized buildings). This will add the building height to the DEM. One thing to note is that you will probably ...


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Thanks for the report. I hope that I got it fixed in r62901. Please try again to install the addon as before so that the latest version gets fetched from the Addons repository.


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The r.li suite has been completely rewritten. While in the past it ran in parallel mode, the results were not reliable. The only way was to rewrite it from scratch at the expense of the multi-core approach. Please try a recent (i.e. less than 1 week) SVN snapshot of GRASS GIS 7 to use the now working version of r.li.


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Nine points is a quite small number, so I would use some arbitrary boundary instead of trying to build a complex algorithm that might "go wild". I suggest that you use r.grow.distance in grass to create a distance layer around your points, and to set a threshold that would constraint the size of your study area (for instance, the largest distance value ...


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Please consider to use v.net.path - finds shortest path on vector network or v.net.alloc - allocates subnets for nearest centers. See also the list of available vector network algorithms. The v.distance command will find the shortest direct distance but you likely want to follow the network in order to obtain more realistic distances.



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