Python Reading

• Read the chapter entitled Dictionaries from section "Sparse Matrices" through section "Glossary"

Class Presentations

• Ernesto's JSON materials
• Tom's security materials

Key Ideas

• A dictionary handles sparse data well. For example, consider keeping track of how many times a word occurs in a novel such as The Catcher in the Rye. Only words that appear one or more times need to be stored.

In-Class Activity

• Download and experiment with sparse.py until you understand how it works.

Active Learning

• Modify sparse.py so that function most_frequent works.