Make Your Own Cartogram

A weblog for members of the Canadian Cartographic Association and other individuals interested in all things cartographic

Make Your Own Cartogram

Published Saturday, May 06, 2006 by CCAer | E-mail this post

MAPresso is a free Java applet that creates cartograms and choropleth maps. Provided you can make sense of the somewhat confusing documentation, you can employ shapefiles converted to psc files (using the convertor tool supplied on the website) and export the resultant map to an eps file (supplied in code, of all things). This is not the most user-friendly tool about and didn’t quite make sense to me until I had a look at some of the examples of the tool in use.

The world map is perhaps the most illustrative of the examples and comes in two sizes. It allows you to enter in your own data (with very little indication as to how that should be done or in what order) and to specify the number of “passes” or how much distortion should occur when the cartogram is being created. It also allows you to specify the colours that are be used on the map and how the classes should be divided.

All in all, an interesting tool made for the technical person. This is not a very user-friendly applet.

5 Responses to “Make Your Own Cartogram”

Anonymous on 11:39 PM

Awesome. I need a tool to make a cartogram. Thanks buddy and great blog!
Anonymous on 5:35 AM

Thanks for thoses links, by the way, an intersting project about cartograms :

http://www.worldmapper.org
Anonymous on 9:54 PM

It's choropleth, not chloropleth! Or so my cart prof tells me!
Anonymous on 9:09 AM

The main purpose for this applet was not the construction of cartograms, but the visualization of geographic data on a website. It's a tool for the non-specialist, the idea behind was to bring some cartographic concepts (as the unclassed choropleth map, a thematic generalization approach, and the interactive experimenting with cartograms) to the public. From the side of the accidental user, the applet should be easy to use. I admit that it is really not user-friendly for a content provider who wants to integrate it in a website, or for someone who wants to work with own geometries. I've tried to help people, who wanted to use it, they are still welcome. Of course, it would be best to have a standalone application for doing cartograms - with an easy interface for data and geometry and various cartogram options and algorithms.
Anonymous on 3:23 AM

If you want to make your own cartogram I'd suggest to use the new algorithm by Gastner and Newman. You find implementations at http://www.santafe.edu/%7Emgastner, e.g. an Java implementation by Frank Hardisty (http://people.cas.sc.edu/hardistf/cartograms).