Matplotlib: Difference between revisions

Revision as of 23:37, 7 May 2015

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 start with the data-set created in this morning containing information about edits to the Harry Potter Wikipedia article.

We will then proceed to visualize different aspects of data from the Socrata web API.

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 the CDSW Matplotlib code from [here]

References

matplotlib API reference
matplotlib Examples (many, with source)
Other plotting resources
- 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

@@ Line 5: / Line 5: @@
 In this session, we will explore how to produce clear, informative charts, graphs, and plots with [http://matplotlib.org/ Matplotlib], the most popular toolkit for scientific data visualization in Python.
-We'll be focusing on a dataset drawn from Wikipedia and , containing the names, birth dates, genders, article creation dates, and number of edits, of over 180,000 Wikipedia biography articles.
+We'll start with the data-set created in [http://wiki.communitydata.cc/Community_Data_Science_Workshops_(Spring_2015)/Day_3_Lecture this morning] containing information about edits to the Harry Potter Wikipedia article.
+We will then proceed to visualize different aspects of data from the [http://wiki.communitydata.cc/Community_Data_Science_Workshops_(Spring_2015)/Day_2_Projects/Socrata Socrata web API].
-The dataset used here has been drawn from several sources. The list of biographies and the gender of the biography subjects comes from a datbase called [http://dbpedia.org DBpedia] that is a structured database built from Wikipedia. If determines if articles are biographies from the Wikipedia category system and it determines if the subjects are male or female primarily by looking at whether subject is referred to as ''he'' or ''she'' in the article. Birthdates for people are extracted from the data recorded in Wikipedia in the "infobox" sidebars common to many pages. Data on how people edit Wikipedia is merged onto this dataset from a separate collection of metadata of Wikipedia editing very similar to the one we built for Harry Potter articles the morning.
 === Goals ===
@@ Line 19: / Line 20: @@
 * Exercise your creativity by making your own visualization
-=== Download and test the Matplotlib-with-Wiki-bios project ===
+# Download the CDSW Matplotlib code from [[http://mako.cc/teaching/2015/cdsw-autumn/wikibios.zip here]]
-(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.zip
 === References ===