Mapping Hacks

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Chapter 2, Mapping Your Neighborhood

#21 Map Health Code Violations with RDFMapper

HACK

violation of some kind there; this could be one relatively innocuous citation

for “Holding Temperatures” a degree or two too warm, or a string of viola-

tions including Vermin and Contaminated Equipment. On this map, they all

look the same qualitatively. However, this is hopefully a good illustration of

using RDF as an intermediary format. RDFMapper can also be used to map

web data that is not already presented in RDF, with the help of quick con-

version scripts.

The RDFMapper Web Service in Depth

The basemap parameter passed to the RDFMapper service specifies the URL

of a file in RDFMap format describing the map that is to appear in the back-

ground. This RDFMap file specifies the URL of the image and the parame-

ters of the geographic projection that applies to the image. The image is

either a JPEG or a .swf file. A catalog of maps suitable for use with RDF-

Mapper can be found at http://www.mapbureau.com/viewer. You can also

create your own base maps from existing images by encoding the relevant

projection data in RDFMap format.

The

content parameter specifies the URL of the RDF file to be mapped.

Figure 2-22. The RDFMapper map of San Francisco health code violations