title: How to plot data over a non-rectangular region in Octave?
body: <p>I have three arrays of equal size: <code>x</code>, <code>y</code>, <code>z</code>. I want to plot <code>z</code> over <code>x</code>, <code>y</code>. Problems is, those <code>x</code> and <code>y</code> do not represent a rectangular region, such as what would be in case of using <code>meshgrid</code> function.</p>
  <p>I know I can use something like <code>scatter</code>, but that would graphically only give me the points themselves. What I want is the filled, smoothed picture. So as opposed to this created by <code>scatter</code>:</p>
  <p><a href="https://i.stack.imgur.com/zy6DJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zy6DJ.png" alt="enter image description here" /></a></p>
  <p>I would like something like this:</p>
  <p><a href="https://i.stack.imgur.com/nnr3q.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/nnr3q.png" alt="enter image description here" /></a></p>
  <p>Any suggestion how this can be done? I have a feeling the data must be smoothed out somehow via interpolation or something else prior to plotting which itself should be simple.</p>