GRASS 6 Tutorial/Raster data management

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Raster data management

Data Import

In a similar way to the vector data management, the import and export of raster data is underpinned by GDAL. As such, the modules,* and r.out.* and specifically, and r.out.gdal are used. The module r.extenal can be used in lieu of importing a raster into GRASS.

A Geotiff can be imported into GRASS using the command line (input represents the full or relative path to the raster file you want to import; output is its raster name in GRASS). The same can be achieved using the GUI. input=elev_input_state500m.tif output=elev_input_state500m

Grass raster import.png

Sometimes, you need to define the region of the Mapset to the extent of your raster. For instance, using the above-mentioned example, you would simply:

g.region rast=elev_input_state500m

A common issue that users are faced with is how to import several GeoTiffs? Obviously the above steps can be repeated using the GUI or copy-pasting the command line or more simply using the following BASH for loop:

for file in `ls *.tif`
 do input=$file output=${file%.tif}

Note - that when you run, the full extent of the map is imported