What is it
In the wolf sheep predation model (Wilensky, 1998), three types of agents interact on a grid. Grass continuously grows at each grid location, sheep wander around and eat some of the grass, and wolves wander around and eat sheep. Sheep and wolves both reproduce at some regular rate, and both die eventually if they don't have enough to eat. Parameters control the rates of grass growth, the initial numbers of sheep and wolves, the rates of sheep and wolf reproduction, and how much energy sheep and wolves derive from eating grass and sheep. These parameters can be set to produce a balanced model in which the current quantities of grass, sheep and wolves oscilate up and down but never drop to zero or increase without limit.
This Xholon application is based directly on the NetLogo model. As much as possible, it uses a Javaized version of the exact syntax found in the NetLogo original. The purpose of this is to demonstrate how Xholon can support the turtle geometry, Logo, StarLogo, and NetLogo paradigm.
How to use it
Things to notice
Things to try
Extending the model
This Xholon application demonstrates how to use the NetLogo-like turtle API.
Credits and references
The original NetLogo copyright notice is repeated below.
The same model has also been implemented using Repast: Tatara, E., North, M.J., Howe, T.R., Collier, N.T., Vos, J.R. (2006). An introduction to Repast Simphony modeling using a simple predator-prey example. repast.sourceforge.net/papers/Agent_2006_Repast_Tutorial.pdf