Links for Lecture 20

Logarithm

Properties of Logarithms and Applet

Comparing Logarithm and Exponential Applet

The Matching Problem Applet

Shannon Entropy of English Letters

Morse Code Applet

Links for lecture 20

Text Analyzer

Anotherletter frequency histogram tool

Simon Singh's Letter Frequency Analysis Tool

Textalyzer

Foreign Language Frequency Analysis

The State of the Union in Words: A Look at the 34,000 State of the Union Words Delivered of George W. Bush - New York Times

Read more about the Enigma Machine
Play with the Enigma!
Enigma Simulator

The code book and its cd-rom have a nice chapter on the subject. BTW, our friend Turing was instrumental in cracking this code. The movie U-571 deals with the military operation that allowed the code to be cracked, though it is not very historically accurate. There is a very good BBC movie about Turing and breaking the Enigma code.

Slides for Lecture 3

The slides for lecture 3 are now online, as are all AI office hours.