Wednesday, April 18, 2012

Sage notebook on relations

I filled in for Al Doerr in his class this morning and he asked me to cover some material on relations. So I took that opportunity to figure out how to implement some relations in Sage. It went pretty well. One exception is that in squaring an adjacency matrix of a relation, I'd like to get a simple adjacency matrix with just 0's and 1's. The way I did the calculations, I got the numbers of different paths of length 2 connecting the vertices. That's fine except that the graphs of the squared relations become messy. If anyone knows how to fix this, I'd appreciate the help.

Wednesday, April 4, 2012

Two Part Version of Applied Discrete Structures

Applied Discrete Structures is now available in either a single volume or in a two part version:
Part 1 - Fundamentals
Part 2 - Algebraic Structures
It broken according to how the two semesters of discrete math are taught at UMass Lowell. We did this for a few reasons. One is that many of our students only need to take the first semester. Also, the full version, whether as a pdf or a printed book, is quite large (484 pages).

Information on the one and two part versions (as free pdf's or printed copies from is available on our web site: