Finish openmc.lib implementation and add tests for density multipliers.

Author: nuclearkevin

openmc/lib/cell.py

@@ -244,6 +244,43 @@ def set_temperature(self, T, instance=None, set_contained=False):
 
         _dll.openmc_cell_set_temperature(self._index, T, instance, set_contained)
 
+    def get_density_mult(self, instance=None):
+        """Get the density multiplier of a cell
+
+        Parameters
+        ----------
+        instance: int or None
+            Which instance of the cell
+
+        """
+
+        if instance is not None:
+            instance = c_int32(instance)
+
+        rho = c_double()
+        _dll.openmc_cell_get_density_mult(self._index, instance, rho)
+        return rho.value
+
+    def set_density_mult(self, rho, instance=None, set_contained=False):
+        """Set the density multiplier of a cell
+
+        Parameters
+        ----------
+        rho : float
+            Unitless density multiplier
+        instance : int or None
+            Which instance of the cell
+        set_contained: bool
+            If cell is not filled by a material, whether to set the density
+            multiplier of all filled cells
+
+        """
+
+        if instance is not None:
+            instance = c_int32(instance)
+
+        _dll.openmc_cell_set_density_mult(self._index, rho, instance, set_contained)
+
     @property
     def translation(self):
         translation = np.zeros(3)

tests/unit_tests/test_lib.py

@@ -159,6 +159,29 @@ def test_properties_temperature(lib_init):
     assert cell.get_temperature() == pytest.approx(200.0)
 
 
+def test_cell_density_mult(lib_init):
+    cell = openmc.lib.cells[1]
+    cell.set_density_mult(1.5, 0)
+    assert cell.get_density_mult(0) == pytest.approx(1.5)
+    cell.set_density_mult(2.0)
+    assert cell.get_density_mult() == pytest.approx(2.0)
+
+
+def test_properties_density_mult(lib_init):
+    # Cell density multiplier should be 2.0 from above test
+    cell = openmc.lib.cells[1]
+    assert cell.get_density_mult() == pytest.approx(2.0)
+
+    # Export properties and change density multiplier
+    openmc.lib.export_properties('properties.h5')
+    cell.set_density_mult(3.0)
+    assert cell.get_density_mult() == pytest.approx(3.0)
+
+    # Import properties and check that density multiplier is restored
+    openmc.lib.import_properties('properties.h5')
+    assert cell.get_density_mult() == pytest.approx(2.0)
+
+
 def test_new_cell(lib_init):
     with pytest.raises(exc.AllocationError):
         openmc.lib.Cell(1)