<script src="http://spelprogrammering.nu/simple.js">

function start()
{
  v = 0;
  k = 3;
  n = 7;
  d = 8;
}

function update()
{
  r = k * sin(n / d * v);
  math.polarPoint(v, r, 2, "red");
  v += 0.005;
}

</script>