title: Plot a parametric equation in Matlab
body: <p>I have two sets of data: <code>[t1 ; x]</code> and <code>[t2 ; y]</code>, where the <code>t</code>s are in the same range for both, but possibly taking different values. A simple example:</p>
  
  <pre><code>[t1 ; x] = 
       1     2     4
       1     4    16
  
  [t2 ; y] =
       1     3     5
       1     9    25
  </code></pre>
  
  <p>Here the underlying functions are simple: <code>x = t1.^2</code> and <code>y = t2.^2</code>. My goal is to get a plot of <code>x</code> versus <code>y</code>. Since the values taken by <code>t</code> aren't the same, I cannot simply use <code>plot(x,y)</code>. For the example, since <code>x == y</code>, I should get a line of slope <code>1</code>, but <code>plot(x,y)</code> isn't straight and neither piece has slope 1.</p>
  
  <p>The application is much more complicated than this simple example, and I do not have an underlying function to generate data points. The data are sparse at times, so I cannot afford to lose information by throwing out points that are not in common between <code>t1</code> and <code>t2</code>.</p>
  
  <p>I'm hoping that Matlab has some built in function that can take the two data sets and extract the dependence between <code>x</code> and <code>y</code> leaving <code>t</code> as an unseen parameter. Anyone know of such a function? In lieu of that, I'm open to suggestions for a good way to go about writing one.</p>