A QGIS plugin for creating cartograms based on polygon layers.
This plugin is an updated version of the cartogram plugin by Carson Farmer which is based on an algorithm proposed in the following paper:
Dougenik, J. A, N. R. Chrisman, and D. R. Niemeyer. 1985. "An algorithm to construct continuous cartograms." Professional Geographer 37:75-81
This plugin is based on the template provided by the Plugin Builder QGIS plugin.
Try it out
To see the plugin in action simply import the demo data included with the plugin (Vector → Cartogram → Add demo layer). Then you can click the Cartogram button on the toolbar or select Vector → Cartogram → Create cartogram.
Select the newly added demo layer and the VOTERS field and set the number of iterations to 5. When you click OK the cartogram will be generated in the background.
When the cartogram has been generated it is automatically added to your canvas so you can continue working with it or export it in any of the file formats supported by QGIS.
The algorithm only supports positive values as the basis for creating the cartograms. If your dataset contains zero or NULL values, we try to create suitable replacement values to make it possible to render a cartogram anyway.
- Search for 'An algorithm to construct continuous cartograms' on Google Scholar
- Constructing Contiguous Area Cartogram uUsing ArcView Avenue
- def CreateRubberSheetCartogram
QGIS Cartogram – a plugin for creating cartograms from polygon layers
Copyright (C) 2015 Morten Wulff
Copyright (C) 2013 Carson Farmer
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.