Monday October 22

Finish the butterfly model so that it computes the clumping measure at the end
of the simulation. You can define the clumping measure any way you want, as long
as it is reasonable. In addition to adding code to the model, you should:
1) add appropriate comments
2) in the Information tab, add a brief description of your definition of clumping.

We will look at Chapter 6 next, so try to read at least some of it before
Monday. After Chapter 6, we will start discussion of the projects, so you
might want to start thinking about that.