Software

Authored Software

Software for students

• StateGraphSearch - explore graph search algorithms through animated Google maps
• webcrypt - cryptologically enabled web browser
• cfgrep - context free grammar egrep variant
• JavaCFG - visual parse tree generator for context free grammars

Software for instructors

• JavaGrades - student grades website and personalized email generator
• Administrator's version of webcrypt - allows instructors to auto-generate random personalized instances of ciphertext for students to cryptanalyze online in private directories

Student Projects

Automata Theory

• JasTeX → Turing Machine → Simulation by B. J. Dweck. The program lets you draw the state diagram of a Turing Machine, and then simulate the machine on a built-in simulator. The Turing Machine can be saved in a format that is compatible with the LaTeX document system.
• javatexc : TextFile → BJDweck by Philip Kuperberg. Are you getting frustrated with a the GUI for B.J. Dweck's program? (It's not B. J. Dweck's fault, but the originators of JasTeX!!!). Want a quick and easy way to write up a text file containing Turing Machine transitions and convert to B. J. Dweck's simulator? I recommend that you check out Philip Kuperberg's little program.
• BJDWeck → PDA by Feng-Ting Zhang and Yiding Li. There is a nice pushdown automata simulator that is even able to account for nondeterminism. PROBLEM: the interface for creating PDA's is extremely unfriendly (e.g. the only way to fix a mistake is to start over). SOLUTION: just draw your PDA in BJDweck's program, save to a Gastex file, and run this nifty little program. Then open the PDA file from the provided (debugged) version of the PDA simulator.
• ABCEZ - Applet Based Computability Enlightenment Zone. Created by John E. Cao, Jing Fan, Jing Huang, Shen Li, Yiting Shen and Simin Wang --collectively known as "Mindspring". Lets you simulate DFA's and NFA's in a beautiful Java applet or application.

Cryptography

• JSEncryptor by David Larivierre - a program that lets you obfuscate the JavaScript code used for accessing hidden URL's. It can be used in conjunction with my JavaGrades program to:
  • obfuscate a JavaScript hash function using a semester key
  • generate unique random passwords from the semester key. The passwords are used:
    1. to de-obfuscate the JavaScript
    2. as inputs of the de-obfuscated script the outputs of which will be the hidden filenames

Group Theory

• Jennie Finkel wrote some nice Java code for attempting to disprove the Hanna Neumann Conjecture. You can download her code from this directory.