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Predator-prey model - Index

Here is a simple predator-prey model of rabbit and fox populations.

To show how Excelsior makes it easy to generate different sizes of spreadsheet, here's a version with only 10 timepoints, and one with 1000 timepoints.

I derived the Excelsior code from a predator-prey spreadsheet at Norm Herr's site, www.csun.edu/science/ref/spreadsheets/xls/predator_prey.xls, by reverse-engineering it into Excelsior code. This documents the spreadsheet clearly, and can be seen at the links below:

• foxes
  This file calculates the birth rate, death rate, and population of foxes. The link above is HTML generated by Literate Excelsior: its original is here.

• rabbits
  This file calculates the birth rate, death rate, and population of rabbits. The link above is HTML generated by Literate Excelsior: its original is here.

• time
  This file defines the type 'time' over which most tables run. It also displays the values of the time points. The link above is HTML generated by Literate Excelsior: its original is here.

• layout
  This file defines the layout for the spreadsheet. The link above is HTML generated by Literate Excelsior: its original is here.

As an experiment, I have put up copies at the Web-based spreadsheets EditGrid (http://www.editgrid.com/user/popx/Rabbits), Google (http://spreadsheets.google.com/pub?key=ph3XeP3_Siojaoyf6L8IbXQ), Numbler (https://numbler.com/6Ep2P23SqgJlkRZa), and Zoho (http://sheet.zoho.com/public.do?docurl=dGmtEuFpaF0%3D&name=FPLvAgHUGiI%3D).

[ Repository of Excelsior examples | More about Excelsior | Jocelyn Paine's home page ]