London Robberies Heatmap

[Alan Leslie]

http://www.alfi2fe.co.uk/RobberyHeatmap.html

The data is organised on a month by month basis so the most interesting thing to do is to drag the timeline to the start of a new month to see the transition.

The data was generated with Quantum GIS using the tutorial - http://qgis.spatialthoughts.com/2012/07/tutorial-making-heatmaps-using-qgis-and.html. The data files are rather large, it loads OK on my broadband connection but may be slow on connections with low bandwidth.

I've tried (and failed) to get the polygons drawn the way I want, that is to have the red on top of the yellow on top of the green on top of the blue.
I tried setting the zindex, making sure that the dataset order is the same as the required drawing order and having the first coordinate of the polygon be the most westerly/easterly etc. (I had read somewhere that google maps implicitly sets the zindex given the lat/lon).

Nevertheless I think it is still just about usable.

Alan