Scikit Image Marching Cubes
<p>I'm using the Scikit Image implementation of the marching cubes algorithm to generate an isosurface. </p>

<pre><code>verts, faces,normals,values = measure.marching_cubes(stack,0)
</code></pre>

<p>generates the following error: </p>

<blockquote>
  <p>ValueError: need more than 2 values to unpack</p>
</blockquote>

<p>but </p>

<pre><code> verts, faces = measure.marching_cubes(stack,0)
</code></pre>

<p>works fine so it seems the algorithm is simply not generating the values for <code>normals</code> and <code>values</code>. Has anyone had any experience with this type of issue?</p>

<p>Furthermore, I don't understand the need for the <code>faces</code> output of the algorithm, as a set of 3 vertices for each triangle in the mesh should be sufficient to describe the isosurface?</p>