Monthly Archives: June 2012

June 27, 2012 · 7:12 pm

Qgis – Color to layer attribute

Recently I was working with some data layers in QuantumGIS, playing to decide the proper color combination for my visualization. The result had to be presented in a web environment using OpenLayers.

The point is. I define and check the visualization in Qgis, and then I want to export the results to be served as a OpenLayers Vectorlayer, or as a Mapserver layer. Of course, with the color defined in Qgis.

Openlayers and Mapserver give the option to read the color from an attribute value (here and here). Maybe there is an easier way, but in this case I developed a small plugin to export the current visualized color into a specific layer attribute.

Screenshots

: Color to Attribute – Icon in Qgis main screen

: Main window of the plugin. Select layer and attribute

: Creating a new attribute to fill with the color value

: Feature list after adding the new attribute

humm… more

3 Comments

Filed under code, curious, gis, Maps, tools

Tagged as attributes, color, plugin, python, qgis, qgisplugin, qt, quantumgis

June 19, 2012 · 3:18 pm

Europe Countries – DbPedia+SPARQL+Python

Introduction

DBpedia is a project that aims to extract structured information from Wikipedia. They generate RDF information that can be queried in different ways, one of this is using the SPARQL query language.

In this post I’ll show how to query Dbpedia using a python SPARQL wrapper to obtain all the Wikipedia points of places in Europe. The post explains it step by step, you can fork the code at my github.

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NOTE from the future:
the original code was Europe.py. The closest actual code would be alldbpediapoints.py
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