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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“Missing dependency.This algorithm cannot be run :-(” QGIS + GRASS Windows 7

Windows 7, OsGeo4W pack installed including QGis 2.4.0 and GRASS. I Qgis when i try to execute a GRASS geoprocessing algorithm i get this popup: "Missing dependency.This algorithm cannot be run :-( ...
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Convert a mask image to polygon shape file using GRASS

I used image classification technique in GRASS GIS v7 and generated the image mask below in which white area has NULL value and red area contains 1. I am going to clip those red color areas in a ...
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77 views

List the projection & datum of all the files in a folder

In QGIS/GRASS, is it possible to list the projection details of all the shp,tab,dxf files in a folder ? We are having 100 - 150 files in too many folders. We would like to create a table of Proj ...
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28 views

nr of cells between cells

I want to do the following: I have a set of cells with the value 1, and a set of values with 2. I want to calculate for each cell [2] the distance - ideally number of cells - to the nearest cell 1. ...
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296 views

GRASS 6.4.3 installed with QGIS not working

I'm new to QGIS and GRASS. I'm trying to do an image classification and it seems that the method I need is not within the GRASS toolbox in the QGIS . So I decided to use the standalone GRASS version ...
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114 views

GRASS module g.copy returns irrational outputs

I took this as reference, Moving raster to different mapset GRASS GIS, and I use pyscripter to use GRASS module g.copy from outside, import os import sys #set up GRASS environment variables ...
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164 views

Can one batch-automate the creation of QGIS heatmaps?

I have 4k point shapefiles, from which I would like to generate heatmap TIFFs using the QGIS heatmap plugin (or a functional equivalent featuring triweigth, radius and cell size selection). Is there ...
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200 views

libfreetype-6.dll lost when using GRASS command line

Update#1: Following the instruction of Sorin Călinică, I have installed libfreetype-6.dll using the OSGeo4W Network Installer, and the command d.rast can launch successfully. I am using GRASS ...
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644 views

How to import R-generated .gri/.grd raster files in GRASS?

I received data in .grd + .gri format, where the first one is a small text file and the second one (having the same name) is a binary file. I am unable to open them in GRASS/QGIS. Any hint ? Missing ...
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113 views

display 3D raster/vector in GRASS 7.0 from command line

I am using GRASS 7.0 on ubuntu linux 12.04 x64. I am working through some GRASS tutorials and am able to get a 3d raster to show up when I use the GUI. However, I cannot get the command line interface ...
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285 views

Apply r.neighbours or Neighbourhood analysis (LecoS plugin for QGIS) to 3000 rasters

I need to apply r.neighbours or Neighbourhood analysis (QGIS plugin LecoS (or equivalent) to 3000 rasters and define a neighbourhood of 5 x 5 and calculate the mean. I suppose I need to create a ...
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377 views

How to define correctly the Grass region in Qgis

I know that my question could be pretty basic for some of you. I am trying to learn GRASS. I have some raster layers and a vector file in EPSG 32614. Using the grass plugin I defined a new map set, ...
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219 views

How to get the direction raster from r.walk or r.cost

I am trying to use r.cost and r.walk and r.drain to calculate the shortest path from an archaeological site to the nearest basalt source. I am using all this algorithms with the processing toolbox (I ...
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1k views

install GRASS Addon in with QGIS

Win 7 QGIS 2.0 GRASS 6.4.3 Hi everybody, I want to install some GRASS-Addons to use them in QGIS. Therefore I run GRASS-Plugin in QGIS an open the GRASS-Shell type: g.extension GRASS opens then i ...
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180 views

QGIS Grass Plugin fails with r.cost.vect

I tried the following in QGIS with the Grass Plugin: r.cost input=preCostSurface@albi start_points=OSMroads@albi output=cost0109 max_cost=0 And I get the following error: Dev note: Adapted sites ...
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154 views

Getting started with 'shell scripting loops' in GRASS

I'd like to work through the MODIS-Aqua example here. But typically the hardest bit is getting off the ground. What specifically does it mean by 'shell scripting'? is it referring to the command ...
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265 views

Grass 7 .las data import problem

I compiled Grass7 on Ubuntu 12.10, with liblas in order to run r.in.lidar and v.in.lidar. I now want to import .las data; the option in file -> import raster data -> LAS LIDAR points import is given ...
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340 views

Data management in GRASS from command line?

I'm trying to import a large set of raster files into GRASS. The GUI import tool works fine for a handful of files, but it appears to require that I click the "Layer id" checkbox for each individual ...
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140 views

Error using Grass v.net

I'm trying to connect my network to a points layer with a threshold of 4500 meters. I have about 11000 or so entries in my polyline and about 24 in my points layer. I have alreday used v.distance, ...
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277 views

GRASS-QGIS Linking error

I need few customizations over grass and would use qgis gui for accessing grass. I am building qgis with grass enabled (WITH_GRASS=TRUE). While I am doing that I get the following. Any help is greatly ...
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233 views

Undefined reference errors installing GRASS addon

I am trying to install the r.geomorphons GRASS addon (available from http://sil.uc.edu/pdfFiles/jarek/r.geom.zip) in GRASS. I tried on Windows but gave up and decided the best thing to do was to try ...
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139 views

extract data from several images to different shapefile columns using GRASS

I am now working in grass and I want to extract raster values from several images to a shapefile. I have already created the columns in the .shp where the raster values will be stored but I am facing ...
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55 views

Watershed other than stream ( between two points)

Is there any method available to demarcate watershed for a location other than stream? I mean, if I want to find out the watershed for a place, where no stream available but, sheet of water can flow ...
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233 views

How to apply v.transform on a set of vector layers (GRASS 6.4)?

I have 64 vector layers, all of them must be warped using the v.transform module; the pointsfile is the same for all vectors. How can I apply the transformation recursively to all layers? I'm not ...
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3k views

How to convert a regular point grid to raster? [duplicate]

Possible Duplicate: How to convert a point grid to a raster? I´d like to convert a regular grid (25 meter) of points (XYZ) to a raster. I have tried the GRASS-tool r.in.xyz but I always get ...
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975 views

Interpolation of contours (from one “main-contour-shapefile”)

I calculated, that the best and smalest possible äquidistance (equidistant) for my map is 30m. After I generlized my DHM, I extracted contours of a intervall of 30m and smoothed them. Now I have my ...
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2k views

How to calculate the average value of a raster within polygons?

I am using the GRASS plugin in QGIS. I am trying to calculate the average value of a raster dataset within a set of polygons. I have created a new mapset and have imported both the vector and ...
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98 views

mapping number of days a site is flooded from daily inundated areas maps

I have a set of daily inundated area polygons and would like combine them into one map that can give me a map showing the number of days a site remained inundated. I am unable to figure out any ...
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450 views

Why can't r.patch find the rasters?

I have elevation rasters which loaded just fine in a GRASS session. They represent adjacent areas, so I want to meld them into one raster. I ran r.patch using the GRASS GUI, and it would only accept ...
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107 views

v.dissolve (and other scripts) not in GRASS path

I see that I have the v.dissolve module in my grass64/scripts dir, but it is not found in my path from the GRASS command line. I have the GRASS_ADDON_PATH environment variable set: ...
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116 views

How do I convert my coordinates to the limit of geographic region (outer edge)?

I am trying to use r.in.bin. The parameters of north, south, east, and west needs values: north=float Northern limit of geographic region (outer edge) south=float Southern limit of geographic region ...
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640 views

How to import .flt files into GRASS?

I am trying to import a raster file (.flt) into GRASS. The raster file (.flt) was generated from HEC-RAS. The said raster format cannot be imported into GRASS (it shows the error "file not ...
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628 views

Win7 GRASS 7 & i.landsat.toar

Hello has anyone got experience running i.landsat.toar ? The output files I get are empty, the command takes but a moment to complete. However when run in verbose mode all the calculations are done, ...
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247 views

The resulting maps from a r.mapcalc script is not computed properly

This post is a continuation of my other post Why is my controlling shell script not working?. I created another post because this contains a separate issue that I encountered with the same scripts of ...
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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?
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17 views

Creating input node file for V.net.salesman in GRASS?

I have imported line vector layer and point vector layer(12 points) to grass using v.in.ogr. Now i want to use v.in.salesman to find shortest path between these 12 points, but i couldnt input ...
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42 views

How to use r.mapcalculator to change values within a raster cost map to negative

I have created a cost map in r.cost module in GRASS (through QGIS). This is actually a distance map from a protected area and distance from protected area has been calculated in both directions. How I ...
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42 views

GeoTiff exported using GRASS will not open in other programs

I am trying to export an image group as a multi-band GeoTiff using the r.out.gdal module in GRASS. For some reason I cannot get ArcGIS to recognize my GeoTiff exports. I have tried opening the file in ...
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75 views

How to have newly added lines split existing lines where they intersect, using QGIS

I have a line shapefile where the lines form a closed polygon. Using QGIS (2.8 on OSX 10.7) I would like to add lines to the layer, basically splitting the polygon into quadrants. Then, I will need ...
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34 views

Duplicated vertices in contour features of GRASS?

I use GRASS to produce contours from DEM (r.contours for SRTM rasters). They looks fine, but most of the line features occures to be duplicated; i.e. verticies duplicated. Here are pictures of output ...
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77 views

What's the right way to calculate the scale parameter value for r.relief in GRASS?

I have a little doubt about the way I should calculate the value of the "scale" parameter in the r.relief command in GRASS. In the description section of the r.relief page of the GRASS manual I read: ...
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65 views

Old question without answer: R.Neighbors with large neighborhoods?

I'm working on the same theme as User 32882, and I'm new here. I have the same problem, and update his question with more details. Old question: "I'm running into problems running the r.neighbors ...
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1answer
92 views

G_realloc: unable to allocate 46320000 bytes of memory while managing large .xyz through v.in.ascii

I tried to convert large (~180MB) .xyz file into vector through v.in.ascii in QGIS Brighton (2.6.0) Grass plugin (it should be Grass version 6.4.3). The "primitive registration" stage lasted very long ...
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107 views

Trouble importing NumPy in GRASS. Architecture

I can't get GRASS to work on my system, and after doing some digging I think it is related to me using 64-bit python. I'm not really sure. I get this message... This module requires the ...
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191 views

How to visualize a point cloud in 3D with GRASS?

I'm new with qgis and grass so I'm sorry if there is a straightforward answer for this question but I can't seem to get it done. I've imported a pointcloud into qgis from a datafile. Now i'd like to ...
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60 views

Error in executing commands in GRASS GIS

I'm using Grass 6.4.3RC2. I have a problem because when I execute the command: r.radcov csv_file=cell_list_hataDEM_umts_amc_testTEST.csv dem_map-AlbSRTMdem@PERMANENT clutter_map=AlbClut@PERMANENT ...
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86 views

tutorial for deriving solar insolation estimates from high resolution Digital surface model

I want to estimate solar insolation using grass gis. I have a high resolution DSM generated from Large Format Digital camera.Being a novice in this field i Would like to have a tutorial and steps to ...
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39 views

How to change GRASS language within QGIS?

I use GRASS plugin inside QGIS on Japanese version of windows 7 x64. As I start GRASS tools, all the content show in English but when I try to execute a tool, tools option dispalys in Japanese ...
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112 views

Export GRASS raster as GeoTiff : nodata values exported as -nan (what happens in R?)

I am using the package raster to work with GeoTiff raster files which I expoerted from GRASS using r.out.gdal. GRASS assigned the value -nan to some raster files (type FLOAT32) for missing values. ...
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many add-on don't works GRASS 6.4.3

I use GRASS 6.4.3 on windows 7 64 bit. GRASS has been installed with QGIS 2.6.1. I have added r.stream.* adds-on by SVN. For each add-on, messages of installation were : OK. But when I try the ...