title: How to get principal curvature of a given mesh?
body: <p>I have a problem of getting principal curvatures from a given mesh (of a shape).</p>
  
  <ol>
  <li><p>I am trying to use 'patchcurvature' method from Matlab file exchange. However, the method always given the positive curvatures. I think it might be that the method considered the mesh as separate patches, and calculate the principal curvatures for each patch.
  [~,~,Dir1,Dir2,PrincipalCurvature1,PrincipalCurvature1]=patchcurvature(meshFaceVertices);</p></li>
  <li><p>I also tried to use another method from Matlab file exchange called 'surfature'; however, it calculates the principal curvatures of a 'surface' defined by three 2D arrays of points on the surface. I am not sure how to create a 'surface' with 2D point arrays from a existing mesh defined by vertices and faces. There are some methods convert surface to mesh but not the other way around...</p></li>
  </ol>
  
  <p>Any ideas would be appreciated. Thanks so much and Happy New Year!!!</p>
  
  <p>Best,
  A.</p>