Visualizing data with ggplot from Python

Using my rudimentary knowledge of Python, I was interested in exploring the use of rpy2 to eventually be able to bring together spatial data analysis done in Python, with some higher level tools in R – in this case the powerful graphics library ggplot2 to visualize the results.

My setup is Mac OS 10.7.3, Python 2.7, R 2.14. (R needs to be compiled with ‘–enable-R-shlib’, which the official CRAN binary for Mac is). Also required are Xcode and NumPy.

There is no binary for rpy2 for my configuration available, so I downloaded the source (2.2.3). Extract somewhere, change into the rpy2-2.2.3 directory and install with:

sudo python build install

The Python code below takes a csv file (output from a some prior geoprocessing done with ArcPy) and produces a graphic with a map and a scatterplot – see the comments for further details.

Data can be downloaded here.

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