Working with external data in GRASS 7
This page explains how to work with external data in GRASS 7.
- (to be expanded)
Raster data
External raster data can be linked via r.external. List of supported formats can be determined by
r.external -f
To link file-based data formats, eg. GeoTiff
r.external input=ncrast/urban.tif output=urban
Vector data
External vector data can be linked via v.external. List of supported formats can be determined by
v.external -f
To link file-based data formats, eg. ESRI Shapefile
v.external dsn=ncshape/ layer=railroads output=railroads
Assuming that 'railroads.shp' is located in directory 'ncshape'.
Write access
The module also supports write access to the external data (currently only geometry can be edited). Showcase bellow:
v.external dsn="PG:dbname=grass" layer=obce_b output=obce_b
v.out.ascii input=obce_b where="cat < 10" --q
-742600|-1043000|1 -728486|-1079285|2 -698411|-1095121|3 -716384|-1083350|4 -694125|-1101920|5 -706726|-1097059|6 -732348|-1074146|7 -730615|-1084553|8 -713628|-1086298|9
v.external.out dsn="PG:dbname=grass" format=PostgreSQL
v.transform -w input=obce_b output=obce_b_jtsk xscale=-1 yscale=-1
v.out.ascii input=obce_b_jtsk where="cat < 10" --q
1043000|742600|1 1079285|728486|2 1095121|698411|3 1083350|716384|4 1101920|694125|5 1097059|706726|6 1074146|732348|7 1084553|730615|8 1086298|713628|9
Using wxGUI
From menu
File -> Link external formats
or from toolbar in Layer Manager.
