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What can you do with GRASS GIS plugin?
The GRASS plugin provides access to GRASS GIS databases and functionalities (see GRASS-PROJECT in Literature and Web References ). This includes visualizing GRASS raster and vector layers, digitizing vector layers, editing vector attributes, creating new vector layers and analysing GRASS 2-D and 3-D data with more than 400 GRASS modules.
Where are the grass data stored in QGIS?
GRASS data are stored in a directory referred to as GISDBASE. This directory, often called grassdata, must be created before you start working with the GRASS plugin in QGIS. Within this directory, the GRASS GIS data are organized by projects stored in subdirectories called LOCATIONs.
How to add a gisdbase to the grass database?
Start QGIS and make sure the GRASS plugin is loaded. In the GRASS toolbar, click on the New mapset icon to bring up the MAPSET wizard. Select the GRASS database (GISDBASE) folder grassdata with the LOCATION ‘alaska’, where we want to add a further MAPSET called ‘test’.
Which is an example of the GRASS plugin?
With the GRASS plugin, you can load vector or raster layers using the appropriate button on the toolbar menu. As an example, we will use the QGIS Alaska dataset (see section Sample Data ). It includes a small sample GRASS LOCATION with three vector layers and one raster elevation map.
Is the grass data model raster or vector?
The GRASS vector data model ¶. So in GRASS, a layer is not a vector or raster map but a level inside a vector layer. This is important to distinguish carefully. (Although it is possible to mix geometry elements, it is unusual and, even in GRASS, only used in special cases such as vector network analysis.
Is there a map algebra in GRASS GIS?
In GRASS GIS the map algebra is available through r.mapcalc module (implemented in C) or its convenient GUI wrapper Raster Map Calculator. The r.mapcalc syntax is specifically designed for raster map algebra and is based on C syntax (Python is C-like language as well).
Where can I find GRASS GIS in ArcGIS?
GRASS GIS analytical modules won’t ask us to provide projection for the output dataset which is a common thing for some ArcGIS tools. In ArcGIS, users often have data in different directories on disk. Basically all geospatial data for GRASS GIS are in the GRASS GIS database (a folder on a disk or network drive).
Where can I find sample data for grass?
More sample GRASS LOCATIONs are available at the GRASS website at http://grass.osgeo.org/download/sample-data/. If you have problems loading data or QGIS terminates abnormally, check to make sure you have loaded the GRASS plugin properly as described in section Starting the GRASS plugin. GRASS data are stored in a directory referred to as GISDBASE.
What are the parts of the GRASS GIS integration?
The integration consists of two parts: provider and plugin. The provider allows to browse, manage and visualize GRASS raster and vector layers. The plugin can be used to create new GRASS locations and mapsets, change GRASS region, create and edit vector layers and analyze GRASS 2-D and 3-D data with more than 400 GRASS modules.
Where do I find the grass icon in QGIS?
If the provider is loaded in QGIS, the location item with GRASS icon is added in the browser tree under each folder item which contains GRASS location. Go to the folder grassdata and expand location alaska and mapset demo.