Quantum GIS, commonly referred to as QGIS, has a new updated release: version 1.8 Lisboa. Recent releases have been named after a different city. QGIS is a bit more user friendly than GRASS. Plus, it also has GRASS functionality along with other tools that GIS users frequently use, such as Python.
So, I put the newest version through a few quick tests. The map below is of Wifi locations in New York City. Via an Open Layers plugin, QGIS allows you to add layers for Google Earth, for example. The WiFi locations were taken from Open Data NYC and symbolized with a custom marker by finding a .svg file of a wifi signal and placing it in the appropriate folder. Next, I wanted to test the progress on a old buggy feature--kernel density.
Unfortunately, based on attempts today and searching Issues in the forum, it appears any updates to the v.kernel did not make it into this release. Why I am sad? Well, kernel density is a basic part of exploratory spatial data analysis. However, fortunately, many already existing spatial tools continue to work great and many general improvements have been made and are listed here.
Lastly, I checked out the attribute data for one wifi spot--turns out the coordinates are correct but the street is wrong (Centre not Center street)! A 60 Center Street is northeast of 60 Centre Street. So again, always be careful with open source data. Clicking on the map below, will open a larger version.
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