CS 312 (W'07, T Th sections)

So I found a couple of things that were easier for me to understand:

Wikipedia Example (this is simpler than the one we've learned. The optimality test is easier if you just check for non-zeros)
http://en.wikipedia.org/wiki/Simplex_algorithm_method

Java applet that does the whole algorithm step by step. (And gives you and answer to check yours against!)
http://www-fp.mcs.anl.gov/otc/Guide/CaseStudies/simplex/applet/SimplexTool.html

Thanks for the tips, drfindley. I found the algorithm in wikipedia and in the java applet sufficiently different from class that it was more confusing than just reading the pdf from class. But being able to compare my answers with the applet's was very helpful and reassuring.

Here are a few tips of my own:

First, be sure to have read at least the implementation section (section 4) of the linear programming notes before getting started on the project. I wasted 4+ hours trying to figure out how to get the indices in B and N right until I read that paper.

Second, the paper doesn't have any examples of actually doing the math using matrices, and although it talks about growing the matrix and vectors to twice their size, it doesn't say where to put all the zeros. So here's the pattern:
A matrix: make it n+m wide and tall, and put the original A matrix data (that is only m high and n wide) in the lower-left corner of that matrix. Some thinking about what each corner of the matrix represents should make the reason clear.
b vector: add n zeros in front of whatever data is there.
c vector: add m zeros to the end of the vector.

Disclaimer: This worked for me. Your mileage may vary.

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