# Simple Pendulum Example

## Dependencies

- sympy 1.0

## Problem

This code determines the equation of motion for a simple pendulum. The pendulum
and defining coordinates are given in the following figure.

<div align="center">
<table class="image">
<tr><td><img src="./pendulum.svg" alt="Pendulum Diagram" title="Pendulum
Diagram" width="200" height="200"/> 
</td></tr>
</table>
</div>

The resulting equation of motion is given in terms of θ and its time
derivatives.

This example is useful as an introduction to defining reference frames, points
and particles in a simple format. This is so that learning the code is not
hindered by a more complex dynamics problem.
