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Questions tagged [grass-gis]

GRASS GIS (Geographic Resources Analysis Support System) is a free, open source geographical information system (GIS) specialized in handling raster, topological vector, image processing, and graphic data. GRASS GIS is a high performance analytical GIS and remote sensing with focus on modularity. Users can process both day-to-day data as well as massive time series.

GRASS GIS logo

GRASS GIS (GRASS) is a user-friendly, powerful, cross-platform Geographic Information System (GIS) application with support for Linux, MacOS X and MS-Windows. News updates are available from the main site.

Commonly referred to as GRASS, this is free Geographic Information System (GIS) software used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization. GRASS GIS is currently used in academic and commercial settings around the world, as well as by many governmental agencies and environmental consulting companies. GRASS GIS is an official project of the Open Source Geospatial Foundation (OSGeo) and is licensed under the GNU General Public License.

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How to delete a map from the GRASS interface?

I want to delete a map that I generated from GRASS. I tried removing a map from the "Map Layers for each display" tab in the GRASS GIS Layer Manager, but it only removed the map from the list and not deleted. I want to delete the map totally that it…
teamAngat
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Saving Command History/Outputs to a file - GRASS

Is there any way to save the commands typed and the outputs obtained in terminal under GRASS GIS to a text file? I have read that GRASS saves history for each mapset but I have no much idea about how to obtain that. Although there is "Save Output"…
Chethan S.
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What are the advantages and disadvantages importing vs linking data in GRASS?

I'm fairly new to GRASS, and only recently discovered the r.external and v.external functions. I'm used to working with R and QGIS where all the data is "external". Typically I keep vector data in PostGIS and rasters in the filesystem. But it seems…
Lee Hachadoorian
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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 for the surrounding area. The PROJ_INFO is name …
levi.fuksz
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How to calculate difference in altitude along lines using GRASS?

Using SRTM altitude information and OpenStreetmap roads, I want to calculate altitude differences (sum of meters uphill and downhill separated = two values) per road element. What would be the fastest way to achieve this?
underdark
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GRASS GIS: How do I run a batch (bash?) script?

I am in a GRASS database (in command shell), where I want to run a loop function. For example, I want to do an operation on many raster files that are in the database. I know this must be done through a txt file. What i am confused about is where I…
anotherObject
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Can I split up v.in.ogr into multiple v.clean commands?

I'm trying to load a large set of polygons into GRASS with "v.in.ogr" and am running out of memory at the "Break Boundaries" stage. I'm wondering if I can break into steps all of the different things that v.in.ogr does to a data set when it is run…
lagerratrobe
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Difference between FCELL, DCELL and CELL in GRASS GIS?

Can anyone clarify for me please the options in the "precision" parameter when calculating slope, aspect and curvature in GRASS GIS. What is the difference between FCELL, DCELL and CELL?
Maria Karypidou
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GRASS v.generalize method=douglas not working as expected

I'm frustrated with v.generalize trying to simplify polygons. Those polygons stem from ArcGIS's raster to vector function (imported into GRASS from Shapefile), so they are pretty zigzag like this: Trying to simplify them with v.generalize…
Lars
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Where to change GRASS GIS wxGUI language?

I use GRASS 6.4.2 on Russian version of Windows 7 x64. As I start wxGUI it is shown in Russian. But I don't like its translation and want to work with English interface. I have no clues how to solve it.
Yaroslav
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Removing small areas only if no adjoining boundary

I'm generalizing some lat/lon data in grass64 and as a precursor to the generalization, I am removing small areas from the data using 'v.clean'. The following command is working well: $ v.clean input=foo output=foo_rmarea_100km tool=rmarea…
lagerratrobe
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Monthly Average Solar Maps (R.Sun) in Grass

I'm trying to create monthly average maps as described in R.Sun in Grass. I have my DSM. In reading the page on OSGEO it mentions that it is possible without showing how. Ideas? I assume I will need to write a script.
psxmi
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Export Region definitions - GRASS GIS

I use two different Landsat datasets in different computers. But the region settings I work is the same. Is it possible to export the region settings in the form of a file in GRASS?
Chethan S.
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Selecting subset of separate bands in GRASS GIS?

As you know landsat data has separate files for different bands. Creating a subset is a wise option to work on region of our interest. Therefore, I used this method to subset my image - d.zoom || g.region g.region -p r.mapcalc *subset*=original But…
Chethan S.
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Install GRASS missing addons within QGIS

I'd like to use r.sun.hourly and r.sun.daily from within QGIS but it doesn't seem to be present in GRASS tools. I tried to install it using g.extension in the GRASS shell, but it says I have to run it with sudo, and sudo g.extension gives command…
Louis
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