Software

Open source GIS tools – QGIS

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I was at the first Data Without Borders Data Dive this weekend, and needed a tool to view and play with some GIS layers. I remembered that this was possible in Open Street Map, and dived into the OSM wiki to find out how. The answer (amongst several other options) was an open-source tool called Quantum GIS (QGIS). Which has been impressing me greatly since I first started playing with it.

Notes to self on this:

    • Loading an OSM map into QGIS needs the OSM plugin (QGIS top menu bar > plugins > manage plugins > Open Street Map plugin) and an OSM map file (there’s a QGIS tutorial on this here – I downloaded the Uganda .osm file from cloudmade).
    • Labels on a map is as easy as double-clicking the layer (QGIS top menu bar> ) and clicking “show labels” in the top left corner of the window.

Loading data from an excel spreadsheet is easy, but you need to enable the plugin for this first (QGIS top menu bar > plugins > manage plugins > Add Delimited Text Layer), then click on the little blue box with commas in it icon that appears in the top icon bar. As far as I know, only csv files can be imported this way, but that’s an easy “save as” from most big excel files.

Loading in a WMS stream (e.g. this http://cernunosat05.cern.ch/arcgis/services/THA/FL-2011-000135-THA/MapServer/WMSServer) is also easy, but you have to remember to click “connect”, then click on the stream names in the window below it, and “” below that.