title: Produce random wavefunction
body: <p>I need to produce a random curve in matplotlib.</p>
  
  <p>My x values are from say 1 to 1000 for example. I don't want to generate scattered random y values, I need a smooth curve. Like some kind of very distorted sin curve with varying amplitude and wavelength. </p>
  
  <p>Does something already exist to allow me to easily do this?</p>