Generic interface for particles

bench/cuds_file_bench.py

@@ -5,7 +5,8 @@
 
 from .util import bench
 from simphony.io.h5_cuds import H5CUDS
-from simphony.cuds.particles import Particle, Particles
+from simphony.cuds.particles import Particles
+from simphony.cuds.particles_items import Particle
 
 particles = [
     Particle(coordinates=(0.0, 1.1, 2.2)) for i in range(10000)]

simphony/cuds/__init__.py

@@ -4,7 +4,8 @@
 from .mesh import Mesh
 from .mesh_items import Point, Element, Edge, Face, Cell
 from .lattice import Lattice, LatticeNode
-from .particles import Particles, Particle, Bond
+from .particles import Particles
+from .particles_items import Particle, Bond
 from .model import CUDS
 from .simulation import Simulation
 from .meta import api

simphony/cuds/abc_dataset.py

@@ -111,9 +111,14 @@ def iter(self, uids=None, item_type=None):  # pragma: no cover
             If uids is None, then all objects are returned by the iterable
             and there is no restriction on the order that they are returned.
 
+        item_type: CUDSItem enum
+            Restricts iteration only to the specified item type.
+            e.g. CUDSItem.PARTICLE will only iterate over particles in
+            a Particles container.
+
         Yields
         ------
-        object : Particle
+        object :
             The object item.
 
         Raises
@@ -180,7 +185,7 @@ def __len__(self):
         Returns
         -------
         count : int
-            The number of items of item_type in the dataset.
+            The number of items in the dataset.
         """
 
     def __contains__(self, item):