It depends on what you mean by a 'heatmap' I'm assuming you have some data of the following form.
lat,lng,value There are 3 different ways. 1)Colored Polygons i.e. (usnaviguide) all you do is average the data which falls within a polygon and then draw a filled polygon with a colour which matches the value. How to do this can be found in the google maps api. This approach is nice and correct however you need to define the appropriate areas. 2)Density maps. This tends to be what people mean by heat maps. There is a commercial service which does this http://www.heatmapapi.com/ but if you want it for free you can use my code http://railsagainstthemachine.blogspot.com/2008/08/google-heatmaps-again.html However please note that this approach is mathematically dubious. 3)Proper krigging / Gaussian process based interpolation http://en.wikipedia.org/wiki/Kriging in my view this is the right way to do heat maps however there is nothing really available at the moment - I have some code which kind of works but has some numerical instabilities which I may open source in the next month or so. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Maps API" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/Google-Maps-API?hl=en -~----------~----~----~----~------~----~------~--~---
