Tag Archives: GRASS GIS

Check out this article ‘Let the four freedoms paradigm apply to ecology’ (but don’t get it from ScienceDirect)

Posted on May 22, 2012 by

There is an interesting letter (Let the four freedoms paradigm apply to ecology) in Trends in Ecology and Evolution by Duccio Rocchini and Markus Neteler arguing that science should use open source software. Basically, using open source software will help researchers … Continue reading →

Posted in Open access | Tagged , , , , | 1 Comment

Checking the analogies of known places

Posted on May 11, 2012 by

On the GRASS user email list, a new script for GRASS GIS was just announced; r.finder. The script can be used to check the analogies of places with known characteristics and to show the most similar areas in the region. … Continue reading →

Posted in GIS, GRASS GIS, research tools | Tagged , , , | Leave a comment

Find and select duplicate values in your vector attribute table

Posted on May 4, 2012 by

Suppose you have a vector layer in your GRASS GIS database and you want to find all duplicate values in one of the columns of the attribute table of that layer? If you are using SQLite or PostgreSQL as the … Continue reading →

Posted in Data handling, GRASS GIS, SQLite | Tagged , , , , | Leave a comment

Sexante toolbox for QGIS

Posted on March 30, 2012 by

QGIS already has very strong analytical capabilities through its GRASS toolbox. Now, this is further extended by a new plugin that offers direct access to the Sextante toolbox. With this toolbox, QGIS can tap into 300+ functions from SAGA GIS … Continue reading →

Posted in GIS, GRASS GIS, QGIS | Tagged , , , , , , | 1 Comment

Add geometry values to vector layer in GRASS GIS

Posted on March 17, 2012 by

In my previous post I explained how to add geometry values to the attribute table of a vector map in QGIS. You can do the same in GRASS GIS. It is slightly more complicated (don’t worry, it is still easy … Continue reading →

Posted in Data handling, GIS, GRASS GIS | Tagged , , , , , | 1 Comment

Start R inside GRASS but keep the terminal prompt

Posted on June 17, 2011 by

I often run R from within GRASS GIS. For example using R as a scripting language to automate GIS analysis. Or to use statistical models in R on spatial data in GRASS. I used to open R in the terminal. … Continue reading →

Posted in GRASS GIS, R computing environment | Tagged , , , , , , | Leave a comment

GRASS GIS: creating cross products of multiple raster map layers

Posted on June 11, 2011 by

I am looking at vegetation distribution in east Africa, using a map we have developed based on historical vegetation maps from the region, and I wanted to know the surface area per vegetation type per country. In ‘spreadsheet terms’, I … Continue reading →

Posted in Data handling, GIS, GIS software, GRASS GIS | Tagged , | 4 Comments

Register yourself as GRASS GIS or QGIS user

Posted on May 11, 2011 by

Never realized, but it is possible to register yourself as a GRASS or QGIS user. See this post how to do this.

Posted in GRASS GIS, QGIS | Tagged , , , | Leave a comment

Importing global rasters in GRASS gives me ‘illegal latitude for North’ message

Posted on May 10, 2011 by

Importing data layers with a global coverage in GRASS GIS might in some cases result in the error message “G_set_window(): Illegal latitude for North”. For example, I got the message while trying to import the GlobCover 2009 (version 2.3).

Posted in Data handling, GIS, GIS software, GRASS GIS | Tagged , , , , , | 1 Comment

Extract values from multiple rasters

Posted on May 4, 2011 by

I got a question how to create a loop function using the “for” command to process Worldclim layers, all with similar names (e.g. bio1-19, tmin1-12, tmax1-12, prec1-12). The loop would need to repeat for each iteration: adding a column with … Continue reading →

Posted in GRASS GIS, R computing environment | Tagged , , | Leave a comment