Added examples on compatibility module

docs/compat.rst

@@ -0,0 +1,71 @@
+Compatibility
+^^^^^^^^^^^^^
+
+The following example illustrates the usage of :code:`compatibility` module:
+
+.. code-block:: python
+
+    from geomdl import NURBS
+    from geomdl import utilities as utils
+    from geomdl import compatibility as compat
+
+    from geomdl.visualization import VisMPL
+
+    #
+    # Surface exported from your CAD software
+    #
+
+    # Dimensions of the control points grid
+    p_size_u = 4
+    p_size_v = 3
+
+    # Control points in u-row order
+    p_ctrlpts = [[0, 0, 0], [1, 0, 6], [2, 0, 0], [3, 0, 0],
+                 [0, 1, 0], [1, 1, 0], [2, 1, 0], [3, 1, -3],
+                 [0, 2, -3], [1, 2, 0], [2, 2, 3], [3, 2, 0]]
+
+    # Weights vector
+    p_weights = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
+
+    # Degrees
+    p_degree_u = 3
+    p_degree_v = 2
+
+
+    #
+    # Prepare data for import
+    #
+
+    # Combine weights vector with the control points list
+    t_ctrlptsw = compat.combine_ctrlpts_weights(p_ctrlpts, p_weights)
+
+    # Since NURBS-Python uses v-row order, we need to convert the imported ones
+    n_ctrlptsw = compat.change_ctrlpts_row_order(t_ctrlptsw, 4, 3)
+
+    # Since we have no information on knot vectors, let's auto-generate them
+    n_knotvector_u = utils.generate_knot_vector(p_degree_u, 4)
+    n_knotvector_v = utils.generate_knot_vector(p_degree_v, 3)
+
+
+    #
+    # Import surface to NURBS-Python
+    #
+
+    # Create a NURBS surface instance
+    surf = NURBS.Surface()
+
+    # Using __call__ method to fill the surface object
+    surf(p_degree_u, p_degree_v, p_size_u, p_size_v, n_ctrlptsw, n_knotvector_u, n_knotvector_v)
+
+    # Set evaluation delta
+    surf.delta = 0.05
+
+    # Set visualization component
+    vis_comp = VisMPL.VisSurfTriangle()
+    surf.vis = vis_comp
+
+    # Render the surface
+    surf.render()
+
+Please see :doc:`Compatibility Module Documentation <module_compatibility>` for more details on manipulating and
+exporting control points