title: Plot normal vector field 3D
body: <p>I am implementing the algorithm for <a href="http://en.wikipedia.org/wiki/Photometric_stereo" rel="nofollow">Photometric Stereo</a> where I have already calculated the normals from a set of images with different light directions.</p>
  
  <p>How can I plot the normal vector field in matlab? I have a matrix of normals of size (N x 3).</p>