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Oracle und SQL


Archive for 'Perl'

PostGIS: find the regions with the highest density

For my perl Module Geo::Heatmap you need to find a the maximum number of point per tile (or rather per bin). You may achieve this by parsing the the logs, or use the Power of PostGIS: To group geographically close points you may use the ST_GeoHash function: with geohash as ( select ST_GeoHash(geom::geometry, 5) st_geohash, […]

Geo::Heatmap for Google Maps

Yesterday I released a new Version of Geo::Heatmap (0.16) it should be available on the CPAN mirror of your choice Please see my older post to the same topic Two major changes: I got rid of Image::Magik (which ain’t fun to install) and replaced it with Imager which installs easily The example provided now uses […]

Generating Heatmap/Density Overlays for Google Maps

Quite often one wants to visualize how your customers/incidents/whatever are distributed geographically. I’ve created a quick hack which does most of the stuff for you. The only obstacle you have to overcame is to encode all your data into long/lat format – Google Geocoder might be of some help. The coordinates have to be stored […]

XML Generation in Perl – how it should have always been

At first big thanks to Mark Overmeer for XML::Compile. I had the pleasure to meet Mark in .nl once – cheers and carry on the great work. Whenever I had to create XML (either with perl or php) I did it one way or the other with some sort of templating toolkit. In php I […]

Scraping web pages in JavaScript with Perl

Sometimes you want to scrape Webpages which contain JavaScript and therefore resist beeing scraped with Web::Scraper or the likes. Imagine some JavaScript code like the following to disguise a email address. function mail() { var name = “mail”; var domain = “”; var mailto = ‘mailto:’ + name + ‘@’ + domain; document.write(mailto); } mail(); […]