{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Modeling and Simulation in Python\n", "\n", "Rabbit example\n", "\n", "Copyright 2017 Allen Downey\n", "\n", "License: [Creative Commons Attribution 4.0 International](https://creativecommons.org/licenses/by/4.0)\n" ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "collapsed": true }, "outputs": [], "source": [ "%matplotlib inline\n", "\n", "from modsim import *" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Rabbit Redux\n", "\n", "This notebook starts with a version of the rabbit population growth model and walks through some steps for extending it.\n", "\n", "In the original model, we treat all rabbits as adults; that is, we assume that a rabbit is able to breed in the season after it is born. In this notebook, we extend the model to include both juvenile and adult rabbits.\n", "\n", "As an example, let's assume that rabbits take 3 seasons to mature. We could model that process explicitly by counting the number of rabbits that are 1, 2, or 3 seasons old. As an alternative, we can model just two stages, juvenile and adult. In the simpler model, the maturation rate is 1/3 of the juveniles per season.\n", "\n", "To implement this model, make these changes in the System object:\n", "\n", "0. Before you make any changes, run all cells and confirm your understand them.\n", "\n", "1. Then, add a second initial populations: `juvenile_pop0`, with value `0`.\n", "\n", "2. Add an additional variable, `mature_rate`, with the value `0.33`." ] }, { "cell_type": "code", "execution_count": 2, "metadata": {}, "outputs": [ { "data": { "text/html": [ "