GRASS GIS (Geographic Resources Analysis Support System) is a free, open source geographical information system (GIS) capable of handling raster, topological vector, image processing, and graphic data.

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Module nziv not found in QGIS 2.10.1-Pisa

I want to use nviz in QGIS2.10.1-Pisa on windows 7 and I always get the same warning message : "Module nviz not found", whenever I click on it in the GRASS tools Modules list. I have tried to ...
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2answers
245 views

Issue while running grass from subprocess

I have a map based web application using geodjango. I needed to display the crime hotspots within a selected polygon area. I found that v.kernel is very good for generating heatmaps/hotspots. So in my ...
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0answers
31 views

“Identity” equivalent in Grass GIS

In ArcGIS and SAGA GIS there is the "identity" tool, which creates a vector overlay and shows area contributions of polygons in shapefile B to the polygons in shapefile A (in the attribute table). ...
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2answers
137 views

How to correctly install QGIS 2.8.3 with GRASS plugin on Ubuntu 14.04?

I already tried to install QGIS 2.8.3 using the procedure described on: http://www.qgis.org/en/site/forusers/alldownloads.html#debian-ubunt, but grass-plugin do not compare on plugin list! I tried ...
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311 views

Using GRASS algorithms in Sextante under ArcGIS Desktop?

Sextante for ArcGIS comes with SAGA modules. I know that I can use GRASS algorithms in Sextante under gvSIG. But how can I use GRASS algorithms in Sextante under ArcGIS Desktop? I tried to look ...
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1answer
867 views

Create a 3D surface from xyz csv using GRASS

Apologies if this is a repeat question guys. I am trying to create a 3D bathymetry surface from xyz data. There is approximately 300,000 points with lat, long and z (depth data). The data is sonar ...
2
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1answer
31 views

GRASS plugin for QGIS2.10 missing [duplicate]

I have installed installed qgis2.10 from source on Centos6.6 however the issue i'm facing is that i am missing the grass plugin form the gui. I have checked the plugin manager, its not listed there. ...
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1answer
64 views

QGIS 2.10 with ubuntugis dependecies Grass issues Ubuntu 14.04

I saw in How to correctly install QGIS 2.8.3 with GRASS plugin on Ubuntu 14.04? how to get Qgis 2.10 running from the non ubuntugis repository with grass features but I'm still having problems with ...
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1answer
309 views

Connecting Grass with R

I need help to connect R with Grass. In RStudio when I send the line: loc <- initGRASS("C:/Program Files/R/R-3.1.0/bin/i386", home=tempdir(), override=TRUE) It says: Error in ...
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0answers
20 views

export several rasters from grass

I'd like to export 127 raster files from grass to .tif in one operation. I already stumbled over this post How to batch export using r.out.gdal command in GRASS but it doesn't work (I don't even know ...
2
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1answer
21 views

QGIS GRASS raster to GeoTiff

First of all: Windows 8.1 QGIS 2.8.2 Wien My problem is that I used the GRASS module r.watershed to delineate watersheds and get flows with a DEM. It worked fine so everything is OK so far. But ...
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18 views

Using Spyder IDE to develop python for Grass GIS, get 'ImportError: No module named grass.script'

I am trying to use Spyder IDE to develop a python script using python library from grass-6.4.3. I run the script below, and get 'ImportError: No module named grass.script' I am using python 2.7, ...
2
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1answer
137 views

Grass 7 no longer works via the Processing Toolbox on Ubuntu

When I try to execute a Grass 7 algorithm via the Processing Toolbox in QGIS 2.10, 2.8.2 or 2.8.1, I get the following error: Missing dependency. This algorithm cannot be run :-( QGIS ...
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1answer
20 views

Can't access GRASS tools in QGIS [duplicate]

I'm running QGIS 2.6 on OSGeo-Live 8.4 Virtual Machine based on Lubuntu 14.04. I've set up a GRASS (GRASS GIS 7) environment in QGIS, and I have a merged .tif file of LiDAR images open in QGIS, so I ...
2
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3answers
489 views

Raster map in different zone () than region ()

I am new to QGIS (just installed QGIS 2.0.1) and am having problems running any spatial analysis tools. I followed the instructions on how to call GRASS tools into QGIS, but when I try to run the ...
3
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1answer
3k views

How to find the watershed area for each point in the river network using DEM?

Update#1: Thanks, Micha, I have followed your instruction and successfully use the modules in GRASS. I use r.watershed to get the basin raster and the drainage line: and I use r.water.outlet to get ...
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0answers
45 views

How do I use r.horizon in QGIS?

I have a raster file I wish to find the horizon angles from. I am currently using QGIS 2.10.1-pisa (the latest updated version) with the GRASS plugin (6.4.3 and 7.0). I have a raster file generated in ...
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1answer
44 views

Extracting area from DEM Raster?

After applying constraints to the DEM I polygonised the raster (using GRASS r.to.vect.area) The result is shown below with a lot of vector with resolution = [30 * 30] Is there any solution to make ...
2
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1answer
93 views

Where is the “Add vector layer”-button in GRASS 6.4.4. plug-in QGIS 2.10.1?

I've just downloaded and installed the new version of QGIS 2.10.1 with GRASS 6.4.4. When opening a new GRASS mapset and importing layers, I missed the button "Add a new vector layer". I've updated ...
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7 views

Sky View Factor of building roofs => Vector algorithm [duplicate]

I'm currently working on a project in which I'm trying to assess the SkyViewFactor of a given roof using building vector data. I've already managed to build a process based on vector rasterization ...
2
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1answer
45 views

GRASS: Landsat 8 GeoTIFF import error

I'm trying to import some Landsat 8 GeoTIFFs into GRASS (in QGIS), and I can't work out why I'm getting this error, or how to fix it. No amount of Googling has been able to tell me anything at all. I ...
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0answers
42 views

Trouble with kernel density estimation

I have been trying to find out how to make the SAGA and GRASS kernel density tools work in QGIS 2.8. I have had a lot of trouble trying to get them to work as they produce useless results seen below. ...
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3answers
49 views

Grass GIS: ArcGIS' “Raster to polygon” equivalent

I've got a small clipped extent of a LANDSAT image and I need to have the single pixels as polygons in order to tell the overlap proportions of overlaying polygons. In ArcGIS I used "Raster to ...
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1answer
32 views

QGIS + GRASS: r.in.gdal “View output” produces “cellhd file (…) does not exist”

I'm working with a recently installed QGIS (2.10.1) + GRASS (6 v2.0) package, and have been working with some rasters and vectors in QGIS that I'd now like to play with using the GRASS tools. I've ...
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1answer
24 views

r.report giving only per-class cell count

I'm trying to extract the count of each pixel value in a raster, like in this question: How to extract pixel value counts from a raster in QGIS? However, when I run r.report (from QGis (2.10) ...
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0answers
40 views

64 Bit Win 8.1 grass 7 missing dependency

I searched for an solution but couldn't find it. Problem is: previous i had an working grass 7 within qgis 2.6/2.8 I know that there were more people with the same issue. When executing a grass 7 ...
4
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4answers
2k views

How to open/display and extract NetCDF files info?

I am working with NetCDF files using R & Matlab and I would like to know if the GIS community is using them. I know that ArcGIS can open & display, however most of the times the results are ...
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1answer
30 views

Grass gis or Qgis trade area?

I know it's possible to make a trade area (service area) in ArcGIS. But Is it possible to make a trade area with a network data set in Grass GIS or QGIs?
3
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1answer
39 views

How can I change the way r.cost and r.drain modules work?

Look at the picture #1. This is my cost surface raster that has only 2 values. Area restricted for path to cross (red one) and area that is free to go (yellow one). As I need it and as I undestand how ...
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64 views

Why is r.sim.water out of memory (ERROR: G_calloc) in GRASS GIS?

I'm having trouble with GRASS GIS. I'm new to GRASS GIS, I have played around and also searched the internet and the Wiki, but found nothing really helpful, so this is my last chance :) I wanted to ...
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29 views

Problems using GRASS tools for topology validation in QGIS

I'm working with a shapefile of Enumeration Districts (Setores Censitários) of the 2010 Brazilian Census. Enumeration Districts (ED) are smallest areas for which Brazilian Census data is available. ...
0
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1answer
41 views

GRASS 7 Cost surface and elevation points development

I'm a new to GIS and I need some help. At the moment, I'm trying to develop an optimal path across an area by using GRASS 7 features. It is very similar to the task given here. The problem is that I ...
3
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1answer
584 views

Solar irradiation calculation using r.sun

I am trying to compute the global solar irradiation for a region and the run times seem to be a bit too high. I have as inputs a Digital Surface Model with the buildings and a Digital Terrain Model ...
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4answers
215 views

Grass toolbar for QGIS 2.10

I don't see the GRASS toolbar in QGIS 2.10 (Pisa). There are still GRASS commands in the Processing toolbox. I know there was some upgrade of GRASS for 2.10. Is the toolbar not available anymore? If ...
1
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1answer
59 views

Compile QGIS from source (with Grass)

I recently decided to reinstall QGIS and build against the latest version of GDAL - something I have been putting off for ages because I suspected it would be a nightmare. Lo and behold it has been, ...
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1answer
335 views

Grass 7 on Ubuntu 14.04. Can't start Grass

I attempted to install GRASS GIS 7 on ubuntu 14.04 using these instructions. When I call grass70 from the command line I get a welcome message and a prompt to continue. I then get two error messages: ...
2
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1answer
135 views

How to use GRASS v.kernel to calculate point densities along a network?

In a road network, I need to select the segments where a minimum of 5 dots occur (1 dot = 1 address) over a distance of 100 m (the image attached illustrates my question). I'm trying to use GRASS ...
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1answer
34 views

GRASS GIS Data display

I have import data vector and raster into GRASS GIS database. I try several projection and i dont know why i cant display the data in Grass GIS. But i can display my data with the grass plugin in ...
0
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1answer
26 views

atmospheric correction using Grass

I am using i.atcorr for atmospheric correction in Grass6.4.4. I would like to add Landsat8 sensor to my project(build). If I copy the iwave.cpp file from grass 7, I get error messages. Do I need to ...
0
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1answer
12 views

how to do horton analyis on single catchment in grass gis

I have generated streams using r.stream.extract and used r.stream.order then I have tun r.stream.basin using inputs from r.stream.order. I am getting multiple basins. How to select a single basin and ...
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1answer
42 views

Identify nodes in GRASS

Apologies if this is a really basic question but I have been unable to sort this out: How do I identify nodes in GRASS? Specifically, I am running a Salesman analysis and get the following error ...
1
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1answer
163 views

How to create least-cost path between two polygons with GRASS?

I am completely a beginner in GRASS but I would like to use it to have the cumulative cost of moving between two polygons. More exactly, I would like to get the smallest cost from any point situated ...
0
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1answer
137 views

GRASS i.landsat.toar returns empty raster

I am trying to use the GRASS module i.landsat.toar. Currently the files created are empty and it spits out: So it seems that it is not picking up something? The location is set to the extent of ...
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1answer
52 views

Elevation data from 3D shapefile of buildings to raster DEM

I have acquired LoD2 building models in the 3DShape format (Polygon ZM). This LoD2 data needs to be prepared for a R-script of solar irradiation calculations on roof surfaces, but which can only ...
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1answer
205 views

Problem opening GRASS GUI: libgeos-3.3.6.so: cannot open shared object file:

I have been using GRASS to process some Landsat imagery but very recently, and as far as I am aware - after having done nothing different or changing the settings, I am trying to use GRASS and on ...
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0answers
14 views

GRASS7. Parallel import shapefiles failed

I am trying to import a 8 ShapeFile to GRASS V7.0.0. Each shapefile's size is between 80 Mb and 300 Mb. For this purpose, I've used multiprocessing in python. I run 4 parallel processes, each one ...
4
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1answer
52 views

How do I count the number of vector lines that pass though a given raster cell?

I am working on a project (currently in GRASS7 though I'm not against exporting to Arc or R or other software if necessary) where I am generating thousands of shortest cost paths (using the r.walk and ...
2
votes
1answer
44 views

How to calculate the 3D length of line segment in QGIS?

I've been looking through all of the GRASS commands in the QGIS 2.10 processing toolbox and it seems like one of these must be able to do this but I haven't found one yet. There is 'v.sample' which ...
3
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1answer
34 views

Simplify / generalization of flow lines

I'm trying to make a model of surface runoff of rain water. I'm using GRASS GIS function r.flow, which generates nice smooth lines of runoff. What I need is edit these flowlines someway to avoid ...
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1answer
17 views

GRASS r.inund.fluv example of input files

Does anyone have an example of input files for the GRASS r.inund.fluv add-on that can be shared. I am asking because I am getting some errors when I am trying to run an the files that I created and I ...