@pimms.value<EOL><INDENT>def edge_coordinates(tess, coordinates):<DEDENT>
return pimms.imm_array([coordinates[:,e] for e in tess.indexed_edges])<EOL>
mesh.edge_coordinates is the (2 x d x p) array of the coordinates that define each edge in
  the given mesh; d is the number of dimensions that define the vertex positions in the mesh
  and p is the number of edges in the mesh.