Community Data Science Workshops (Fall 2014)/Day 3 projects/Matplotlib Session

Visualizing data with Matplotlib and Wiki-bios

In this session, we will explore how to produce clear, informative charts, graphs, and plots with Matplotlib, the most popular toolkit for scientific data visualization in Python.

We'll be focusing on a dataset drawn from Wikipedia and DBpedia, containing the names, birth dates, genders, article creation dates, and number of edits, of over 180,000 Wikipedia biography articles.

Goals

• Get set up to make graphs with Matplotlib
• Learn the basics of the Matplotlib API and workflow
• Practice reading the Matplotlib documentation
• Build a plotting program step by step
• Learn simple ways to distill the essence of a large data set
• Explore the art of visualizing data
• Exercise your creativity by making your own visualization

Download and test the Matplotlib-with-Wiki-bios project

(Estimated time: 10 minutes)

After installing matplotlib, and downloading and unpacking the Wikibios bundle, move into that directory with cd. You can test your installation by running python histograms.py. If matplotlib is install correcting, a chart file named histograms.pdf will appear in the current directory.

Bundle with code for all platforms: http://mako.cc/teaching/2014/cdsw-autumn/wikibios.zipb

References

• matplotlib API reference
• matplotlib Examples (many, with source)
• Other plotting resources
  • prettyplotlib: hip-aesthetic matplotlib plots
  • Seaborn: fancy matplotlib-based visualizations
  • ggplot: port of the R language's ggplot2 library to python
  • D3.js: interactive data visualization for the browser (javascript)

Example topics to cover in Lecture

• line charts
• histograms
• binning
• scatter plots
• heat maps
• axis labeling
• legends