title: how to calculate the period of a Lissajous curve
body: <p>my code for a parametric Lissajous curve:
  <code><pre>
  x = A * sin(v * t);
  y = B * sin(w * t);
  </pre></code>
  How to calculate the period of this curve above? I have read somewhere that it is the least common multiple (LCM) of <code>v</code> and <code>w</code> but I do not understand what this means. The maximum period of a Lissajous curve is <code>2 * pi</code>, and I do not understand how <code>LCM(v,w)</code> would yield a value less than <code>2 * pi</code>. Or is its period <code>pi / LCM(v,w)</code>? Confused...</p>