Butterfly Models

Butterfly Model for In-Class Exercises on Sept. 9

• Download the Basic Butterfly Model

• Download the Enhanced Butterfly Model that we wrote in class.

  I have made a few changes to the enhanced model that are different from what we did in class:

  • I changed the name of the turtles-own variable start-patch to origin to be more concise.
  • I changed the equation for the corridor width from $$ \frac{\text{# patches visited}}{\text{sum}(\text{distance-moved})} $$ to $$ \frac{\text{# patches visited}}{\text{mean}(\text{distance-moved})} $$ because that’s what the book uses in Chapter 5.
  • I define the turtle to be at the top of a hill when its patch is the highest in a radius of 3 patches, rather than the highest of all its neighbors.
  • I add a turtles-own variable at-top? that records whether the turtle is at the top of a hill, and in the to go procedure, I tell the model to stop running if all the turtles are at the top of a hill before it gets to 1000 ticks.