title: How can interpolation result be larger or smaller than the minimal/maximal values of the original signal?
body: <p>If I have a matrix</p>
  
  <pre><code>&gt;&gt; M=[0 0 1 1 0 ]
  M =
       0     0     1     1     0
  </code></pre>
  
  <p>and resize it</p>
  
  <pre><code>&gt;&gt; imresize(M,[1,size(M,2)*2])
  </code></pre>
  
  <p>I get an answer</p>
  
  <pre><code>ans =
           0   -0.0234   -0.0703    0.2031    0.7969    1.0938    1.0938    0.7969    0.2031   -0.0703
  </code></pre>
  
  <p>My original array did not have any value less than 0 or greater than 1.  How come it contains values greater than 1 or values lesser than 0?</p>