Updates to the Python API to support model generation with DAGMC universes.

openmc/cell.py

@@ -27,7 +27,7 @@ class Cell(IDManagerMixin):
         automatically be assigned.
     name : str, optional
         Name of the cell. If not specified, the name is the empty string.
-    fill : openmc.Material or openmc.Universe or openmc.Lattice or None or iterable of openmc.Material, optional
+    fill : openmc.Material or openmc.UniverseBase or openmc.Lattice or None or iterable of openmc.Material, optional
         Indicates what the region of space is filled with
     region : openmc.Region, optional
         Region of space that is assigned to the cell.
@@ -38,7 +38,7 @@ class Cell(IDManagerMixin):
         Unique identifier for the cell
     name : str
         Name of the cell
-    fill : openmc.Material or openmc.Universe or openmc.Lattice or None or iterable of openmc.Material
+    fill : openmc.Material or openmc.UniverseBase or openmc.Lattice or None or iterable of openmc.Material
         Indicates what the region of space is filled with. If None, the cell is
         treated as a void. An iterable of materials is used to fill repeated
         instances of a cell with different materials.
@@ -156,7 +156,7 @@ class Cell(IDManagerMixin):
     def fill_type(self):
         if isinstance(self.fill, openmc.Material):
             return 'material'
-        elif isinstance(self.fill, openmc.Universe):
+        elif isinstance(self.fill, openmc.UniverseBase):
             return 'universe'
         elif isinstance(self.fill, openmc.Lattice):
             return 'lattice'
@@ -278,11 +278,10 @@ class Cell(IDManagerMixin):
                         cv.check_type('cell.fill[i]', f, openmc.Material)
 
             elif not isinstance(fill, (openmc.Material, openmc.Lattice,
-                                       openmc.Universe)):
+                                       openmc.UniverseBase)):
                 msg = ('Unable to set Cell ID="{0}" to use a non-Material or '
                        'Universe fill "{1}"'.format(self._id, fill))
                 raise ValueError(msg)
-
         self._fill = fill
 
         # Info about atom content can now be invalid

openmc/filter.py

@@ -15,7 +15,7 @@ from .cell import Cell
 from .material import Material
 from .mixin import IDManagerMixin
 from .surface import Surface
-from .universe import Universe
+from .universe import UniverseBase
 
 
 _FILTER_TYPES = (
@@ -408,8 +408,8 @@ class UniverseFilter(WithIDFilter):
 
     Parameters
     ----------
-    bins : openmc.Universe, int, or iterable thereof
-        The Universes to tally. Either openmc.Universe objects or their
+    bins : openmc.UniverseBase, int, or iterable thereof
+        The Universes to tally. Either openmc.UniverseBase objects or their
         Integral ID numbers can be used.
     filter_id : int
         Unique identifier for the filter
@@ -417,14 +417,14 @@ class UniverseFilter(WithIDFilter):
     Attributes
     ----------
     bins : Iterable of Integral
-        openmc.Universe IDs.
+        openmc.UniverseBase IDs.
     id : int
         Unique identifier for the filter
     num_bins : Integral
         The number of filter bins
 
     """
-    expected_type = Universe
+    expected_type = UniverseBase
 
 
 class MaterialFilter(WithIDFilter):

openmc/geometry.py

@@ -14,13 +14,13 @@ class Geometry:
 
     Parameters
     ----------
-    root : openmc.Universe or Iterable of openmc.Cell, optional
+    root : openmc.UniverseBase or Iterable of openmc.Cell, optional
         Root universe which contains all others, or an iterable of cells that
         should be used to create a root universe.
 
     Attributes
     ----------
-    root_universe : openmc.Universe
+    root_universe : openmc.UniverseBase
         Root universe which contains all others
     bounding_box : 2-tuple of numpy.array
         Lower-left and upper-right coordinates of an axis-aligned bounding box
@@ -32,7 +32,7 @@ class Geometry:
         self._root_universe = None
         self._offsets = {}
         if root is not None:
-            if isinstance(root, openmc.Universe):
+            if isinstance(root, openmc.UniverseBase):
                 self.root_universe = root
             else:
                 univ = openmc.Universe()
@@ -50,8 +50,7 @@ class Geometry:
 
     @root_universe.setter
     def root_universe(self, root_universe):
-        check_type('root universe', root_universe,
-                   (openmc.Universe, openmc.DAGMCUniverse))
+        check_type('root universe', root_universe, openmc.UniverseBase)
         self._root_universe = root_universe
 
     def add_volume_information(self, volume_calc):

openmc/lattice.py

@@ -488,7 +488,7 @@ class RectLattice(Lattice):
 
     @Lattice.universes.setter
     def universes(self, universes):
-        cv.check_iterable_type('lattice universes', universes, openmc.Universe,
+        cv.check_iterable_type('lattice universes', universes, openmc.UniverseBase,
                                min_depth=2, max_depth=3)
         self._universes = np.asarray(universes)
 

openmc/universe.py

@@ -4,6 +4,7 @@ from collections.abc import Iterable
 from copy import copy, deepcopy
 from numbers import Real
 import random
+from xml.etree import ElementTree as ET
 
 import numpy as np
 
@@ -677,10 +678,20 @@ class DAGMCUniverse(UniverseBase):
     def clone(self, clone_materials=True, clone_regions=True, memo=None):
         pass
 
+    def get_all_cells(self, memo=None):
+        return OrderedDict()
+
     def create_xml_subelement(self, xml_element, memo=None):
+
+        if memo and self in memo:
+            return
+
+        if memo is not None:
+            memo.add(self)
+
         # Set xml element values
         dagmc_element = ET.Element('dagmc')
-        dagmc_element.set('id', self.id)
+        dagmc_element.set('id', str(self.id))
         dagmc_element.set('name', self.name)
         dagmc_element.set('filename', self.filename)
         xml_element.append(dagmc_element)