code: def test_vertices_to_triangles():
      cube_tri, cube_vts = create_cube()
      vts_w = np.ones([len(cube_vts)])
      tri_w = vertices_to_triangles_values(cube_tri, vts_w)
      npt.assert_array_equal(tri_w, 1.0)
  
      # weight each vts individually and test triangles weights
      for i in range(len(cube_vts)):
          vts_w = np.zeros([len(cube_vts)])
          vts_w[i] = 3.0
          tri_w_func = vertices_to_triangles_values(cube_tri, vts_w)
          tri_w_manual = np.zeros([len(cube_tri)])
          # if the current weighted vts is in the current triangle add 1
          for j in range(len(cube_tri)):
              if i in cube_tri[j]:
                  tri_w_manual[j] += 1.0
  
          npt.assert_array_equal(tri_w_func, tri_w_manual)
  
imports: import numpy
  import numpy.testing
  from dipy.tracking.mesh import triangles_area, random_coordinates_from_surface, seeds_from_surface_coordinates, vertices_to_triangles_values
label_desc: Use image node_id 4 for calling a global function with example usage: test_vertices_to_triangles() without return types