Monthly Archives: May 2012

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

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 to test, reproduce and build upon work of others, while being (more) sure that the code / algorithms they are using are robust and reliable. Continue reading

Checking the analogies of known places

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. The output is a map  containing all cells with the same combination of thematic maps parameters of the non-zero cells in the input map. You can find the script and documentation here.

 

Poverty maps on HarvestChoice

Data on poverty levels, important for amongst others development study, yet very difficult to get. Sure, you can get global statistics from e.g., the FAO, Worldbank, here or here. But these give you highly aggregated data (mostly by country), not the sub-national level data often needed.

Luckily for those that need sub-national level data, HarvestChoice published in 2010 global sub-national poverty maps. The maps give the distribution of various poverty indices at sub-national level. More recently, Continue reading

Find and select duplicate values in your vector attribute table

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 database back-end (and you should), this is easy using a SQLite statement. Suppose you have the table sp1th and the column value with duplicate values: Continue reading

Update to Ubuntu Preise Pangolin

Just though I share some first impressions about my upgrade to Ubuntu 12.04 (Precise Pangolin). The upgrade process itself wasn’t the best experience ever unfortunately. After the upgrade, I couldn’t even start up anymore. As it turns out, during the update process my GRUB bootloader got corrupted. After a bit of searching, I found an easy solution: the Boot-Repair disc. Simply download the ISO and burn it on CD (yes, you do need access to another computer). After booting my computer using the CD, Boot-Repair let me fix the issues with a simple click.

Having that out of the way, I could finally have a look at the changes.  Continue reading