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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Adding GeoEye1 sensor to grass i.atcorr

Following the instructions, I've updated the iwave.h and iwave.cpp files using the official spectral responses from DigitalGlobe (In the iwave.h file I don't know if it's necessary to use more ...
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0answers
13 views

Error using grass script v.lidar.edgedetection

I'm in trouble with the grass script v.lidar.edgedetection. When I try to filter an xyz format dsm the script starts but at the end of it an error message appears (see attached image). Somebody ...
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3answers
36 views

How to export a GTiff with its GDAL colour table, in GRASS, which is suitable for Adobe Illustrator?

I've created a new raster in GRASS, starting from a dem and using the commands r.relief and r.shade. Now I would like to export this new raster as a georeferenced image and import it in Adobe ...
3
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1answer
450 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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11 views

solar radiation r.sun

I have a dsm and dem for an area. When I try to run r.sun module to calculate solar radiation I receive this error message in the picture. This problem does not occour when I don input slope and ...
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3answers
420 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
37 views

Grass NVIZ has no output in QGIS 2.8.1 ubuntu 14.04

I am trying to use the Grass7 NVIZ algorithm from the QGIS 2.8.1 toolbox, on ubuntu 14.04. I have enabled Grass7 in the QGIS processing preferences. I have compiled Grass7 from source, and Grass ...
3
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1answer
1k views

How to split line at a specified distance and getting coordinates of start and end points of each line segment?

I tried v.split in GRASS: and my notebook ran a lot of time but showed this error:bad allocation, then I click "OK", and got nothing. Are there other ways to split lines?and I hope to get 2 new ...
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1answer
216 views

How to interact with GRASS GIS vector map topology “level/layers” from terminal/command line?

Is there anybody out there that can maybe assist in the most simplest form of code to call on command line to "export topology" (which is level 2 information in GRASS) as separate spatial data, as ...
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8 views

What causes v.net connect “Failed to find intersection segment” and how to fix it?

In GRASS 7, when running v.net connect, I get the ERROR: Failed to find intersection segment and no output is generated. The only mention of this error Google found is in the source of connect.c What ...
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128 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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367 views

Can't launch GRASS GIS 6.4.3 GUI on windows 8.1

As title, I downloaded GRASS GIS from this website: GRASS GIS - Home, and I choose winGRASS 6.4.3 standalone installer to download. After I installed, I click on its icon: I can't launch it even ...
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39 views

How to build a GRASS network with node IDs from the line dataset?

I have a dataset of street network links (line geometries). Each network link has a link id, start node id, and end node id attribute. I want to use this network in GRASS, so after importing the ...
2
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1answer
37 views

Looping for importing and interpolating a lot of LIDAR files?

I'm quite new to Grass Gis and I'm trying to make DEM (digital elevation model) for modelling flooding. I have 170 *.xyz files, which need to be scanned for extents (r.in.xyz -s input=...\filename.xyz ...
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156 views

QGIS 2.8 problem accessing GRASS commands

QGIS 2.8.1 Win7 64 bit installed with osgeo4w-setup. I’m trying to run GRASS commands on a LIDAR raster layer but I get the following message: Missing dependency.... GRASS not installed in your ...
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2answers
484 views

How do I reproject one raster to match another's in GRASS

I have two raster layers, A and B, which have information about the same location but have different projections and datums. How can I reproject layer A to match the projection and datum of layer B? ...
2
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1answer
715 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 ...
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2answers
903 views

How can I calculate the vertical distance to the nearest water?

Summary: I would like to create a raster where each cell contains the vertical distance to the nearest water (a decent approximation would be acceptable). The problem is that I'm not sure how to go ...
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21 views

Command Grass in QGIS not work

When I use r.contour or other Grass commands in QGis, I have this error message. Why?
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1answer
13 views

hdf-eos5 file format import in grass

I want to import AURA-OMI ozone level3 data which is available from http://giovanni.gsfc.nasa.gov/giovanni/ .The data is in hdf5 format. The extension is .he5. Do anyone know how to import in grass. ...
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1answer
229 views

No such file or directory PERMANENT\\MYNAME from Python+Grass?

I have an existing Python script that processes raster images with Gdal / Numpy. Now I want to extend the script with Grass. The python script is developed on Windows 7 with Eclipse/Pydev. The script ...
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28 views

What's the best neighborhood size to smooth the ASTER GDEM v2, resampled at 1m res, in GRASS with r.neighbors?

Basing on your experience, what neighborhood size could be a good compromise to smooth the ASTER GDEM v2, resampled at 1m res, without affecting too much the edges and the valleys? I have to realize ...
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1answer
44 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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1answer
132 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: ...
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3answers
30 views

Unexpected result converting a vector to a raster in GRASS 7.0.0

My purpose is to create a DEM raster in GRASS 7.0.0 starting from a shapefile containing contour lines. The attributes table has a field named QUOTE_INT containing the elevation as integer. I ...
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1answer
61 views

Running Grass7 in conda environment?

I have Anaconda Python Distribution (Python 3.4.3 :: Anaconda 2.1.0 (64-bit)) installed on Ubuntu 14.04. I would like to create a conda environment for running Grass 7. To do that I used: conda ...
2
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58 views

Performance difference between focal statistics (ArcGIS) and neighbor (GRAS or QGIS)

I tested minimum, maximum, and average neighbor (circle radius = 161 pixel) using ArcGIS, GRASS and QGIS: ArcGIS (10.1): it takes only one minute GRASS (6.4.3): it takes 123 minutes for every output ...
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37 views

GRASS GIS r.walk issue

I have been playing around with GRASS GIS to do a simple cost analysis of getting from point A to point B. I have a DEM clipped to the study area, a raster containing the friction costs, as well as ...
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22 views

How to smooth a shaded relief map created with the command r.relief in GRASS 7?

How can I smooth a shaded relief map created with the command r.relief in GRASS 7? I read about the plugin r.denoise but I can only find it for GRASS 6... Thanks in advance. Bryan
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17 views

Is there a max number of cells which r.surf.contour can interpolate in GRASS?

Nothing less, nothing more... I'm wondering if there's a max number of cells which r.surf.contour can interpolate in GRASS, because I have to interpolate a region of 24000 rows x 23000 columns but I ...
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15 views

Reading L1B ASTER in GRASS using r.in.aster

I'm having a problem getting an ASTER L1B to be read in GRASS using r.in.aster. The output the command shows this: (Wed Apr 8 17:49:03 2015) Command finished (1 sec) (Wed Apr 8 17:49:37 2015) ...
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29 views

Grass Processing tools via QGIS : v.clean snap, chdangle, and rmdangle

Using QGIS 2.6 Grass Processing tools, I'm trying to clean up topology on a water network layer. I noticed topological errors when first trying to break all lines on intersections using v.clean break. ...
2
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2answers
116 views

Is d.mon xN deprecated in GRASS in favor of something in the wxGUI?

I'm trying to learn command-line GRASS (6.4.3) using the KyngChaos binaries on a Mac (10.8.4) from Neteler and Mitasova's book, Open Source GIS: A GRASS GIS Approach (3rd ed.). I've learned from this ...
2
votes
1answer
27 views

Generate a raster with a uniform value using QGis

I'm working on a project using the qgis-modeler and i want generate a raster with a uniform value. i'm using r.surf.random function of GRASS which need min and max value but i want have only one ...
9
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1answer
650 views

Kriging on GRASS+R - cannot allocate vector of size 146.5 Mb

I'm trying to do a groundwater elevation map with an Ordinary Kriging on R, but always resulting on the lack of memory cannot allocate vector of size 146.5 Mb allocation (windows xp 32bit). ...
3
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3answers
602 views

Error when creating a new mapset with GRASS in QGIS

When I try to create a New Mapset with the GRASS plugin in QGIS I get an error or the program crashes. QGIS 2.6.1 (32-bit install, Win7). QGIS crashes completely when clicking "Finish" in the New ...
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2answers
59 views

Ls factor, flow accumulation, watershade, relief in Quantum GIS 2.2

I'm a beginner quantum gis. I want to make the LS factor of 30m DEM that I have merge and set the projection in wgs 84/UTM zone 49S (EPSG ; 37249). I'm having a problem when trying to create relief ...
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1answer
51 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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0answers
50 views

Unable to start modules in QGIS GRASS plugin (GNU/Linux Debian)

Recently, the Toolbox of QGIS GRASS plugin can't find modules in my GNU/Linux Debian. When I click on any module, the toolbox reports the message: Cannot find module x.xxx and, after, I have the ...
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2answers
49 views

Extract Elevation of Points from DEM using Python QGIS or GRASS

I am utterly new to GIS, so please bear with me if I am providing incomplete information here. I have a DEM file (.dt2). What I am looking to do is as follows: take a series of points specified as ...
2
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3answers
97 views

Find coordinates of given raster value

I would like to get the coordinates of a raster cell with a given value. I suppose many cells can take the same value, in which case several coordinates should be returned. In my first problem I'm ...
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0answers
45 views

Pansharpening Landsat 8 tiles in Grass 7

I am trying to get some nice looking RGB images for visualization purposes, mainly using as background maps, from the Landsat 8 archive. I was following the tutorial provided by Markus Neteler at ...
0
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1answer
39 views

Conditional calculation - QGIS Raster Calculator or GRASS r.mapcalculator

Is it possible in QGIS either directly or via plugins to do a raster calculation including an if statement? e.g., if raster1 > 0.3, then raster 1 * raster 2, else raster1 x raster3...something like ...
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0answers
16 views

wps-grass-bridge misses essential GRASS tool

I set up a Web Processing Service with 52°North and GRASS (using the wps-grass-bridge). I get a similar result like in the online example here: 52°North WPS Demo I assume it would be similar with ...
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11 views

QGIS WPS plugin misses one parameter

I set up a Web Processing Service with 52°North and GRASS (using the wps-grass-bridge). All went smooth and I get a proper DescribeProcess for i.cluster. As you can see, I need to give the parameter ...
2
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2answers
212 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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1answer
189 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 ...
1
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1answer
15 views

Where to get GRASS module r3.out.vtk?

I'm looking for the GRASS module r3.out.vtk. It's featured on the GRASS GIS manual : http://grass.osgeo.org/grass64/manuals/r3.out.vtk.html But it's nowhere to be found, and neither are r.out.vtk and ...
2
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3answers
1k views

How to delete rings automatically using QGIS/Grass

I'm cleaning up a (very) messy shapefile in QGIS/Grass. I now have several large polygons with numerous (100s) of small rings. Is there a quick and easy way to remove/ fill all these small rings. ...
3
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1answer
271 views

GRASS GIS 7 in QGIS 2.6.1, Windows 7 64bit - Missing dependency

I am using QGIS Brighton 2.6.1. Today I have installed Grass GIS 7.0.0 RC2 to try its topology functions in QGIS. I have activated the provider, set the paths, but everytime I try to use any Grass ...