![]() ![]() ![]() Q: GRASS GIS is giving an "ERROR: Projection of dataset does not appear to match current location". Setting the r.in.gdal memory= option has the same effect as setting the GDAL_CACHEMAX environment variable.īesides the standard tools r.import and v.import, GRASS GIS provides some addition specialized import tools for specific formats: Tile_height * raster_width * band_count * sizeof_datatype In these cases you should increase the memory= option to be larger than: When importing large raster maps with r.in.gdal the default internal settings may be slow, with a large percentage of the CPU locked up in kernel system operations. Importing multiple vector (e.g., SHAPE) filesīulk import of GeoTIFF via menu (files are auto-selected) The wxGUI menu tools offer simplified import. v.external: basic support for external vector data with some topology limitations (all OGR supported formats).r.external: full support for external raster data (all GDAL supported formats).You can just link to the data rather than importing them. Be careful with the region resolution when doing this with vector maps, you may have to run " g.region -a res=" to clean that up and keep it reasonable (for example 2000x2000 rows and columns). You can set the computational region and cell resolution to match a specific map with the g.region module.Īfter importing your data you need to run " g.region -p rast=your_map" or " g.region -p vect=your_map" to set the region bounds/zoom to match that of the newly imported map. You can also read about it in the rasterintro help page. The " computational region" is a very important concept in GRASS and is distinct from the "display window" you see in the Map Display window. The left hand button in the Map Display window will re-render the map if needed. To view a raster map, add it to the Layer Manager with the grid-like button with a (+), to add a vector map to the Layer Manager use the button with lines and points on it to the right of the add raster map button. Otherwise when you go to view the map you could be far away and just see a white display canvas. You will most likely want to right click on the map in the layer list and select "Zoom to selected map(s)". What's next after creating a new location from a data setĪfter the map has been imported you can add it to the display layer list in the Layer Manager window. csv file contains "quoted" strings containing commas, you can use the csv_ script to parse them into a less-problematic form ready for import with v.in.ascii. ( v.in.ogr could too, but it's not as smooth) CSV files from a spreadsheet can be imported with the v.in.ascii module.Many GPS formats can imported with GPSBabel as well using the v.in.gpsbabel tool.Read more about this on the projectionintro help page If you want the data reprojected into something else you'll have to create that target map projection in a location and pull them into there with r.proj and v.proj, or use GDAL's gdalwarp or ogr2ogr command line tools. For each map projection you must create a new GRASS location.Vector formats: File → Import vector data (internally using OGR).Raster formats: File → Import raster data (internally using GDAL).New users: simply use the GRASS Location Wizard.Ĭreate a new location for your data with the correct map projection using the Location Wizard on the main startup screen^, then in the menus (typically GDAL/OGR will automatically detect the file format for you): Supported vector formats via v.import (for example importing Shapefiles).Supported raster formats via r.import (for example importing GeoTiffs).It is the Rosetta Stone of the free GIS world: The primary import/export tool is called GDAL/OGR. GRASS supports many common GIS formats, and many uncommon ones too. 1.5.2 Importing multiple raster (e.g., GeoTIFF) files.1.5.1 Importing multiple vector (e.g., SHAPE) files.1.2 What's next after creating a new location from a data set.1.1 Creating a new location from a data set. ![]()
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