Add a toggle to turn multipole on/off

docs/source/usersguide/input.rst

@@ -267,12 +267,14 @@ based on the recommended value in LA-UR-14-24530_.
 ``<multipole_library>`` Element
 -------------------------------
 
-The ``<multipole_library>`` element has no attributes and indicates the
-directory containing a windowed multipole library. If a windowed multipole
-library is available, OpenMC can use it for on-the-fly Doppler-broadening of
-resolved resonance range cross sections. If this element is absent from the
-settings.xml file, the :envvar:`MULTIPOLE_LIBRARY` environment variable will be
-used.
+The ``<multipole_library>`` element indicates the directory containing a
+windowed multipole library. If a windowed multipole library is available,
+OpenMC can use it for on-the-fly Doppler-broadening of resolved resonance range
+cross sections. If this element is absent from the settings.xml file, the
+:envvar:`MULTIPOLE_LIBRARY` environment variable will be used.
+
+  .. note:: The <use_windowed_multipole> element must also be set to "True"
+    for windowed multipole functionality.
 
 .. _natural_elements:
 
@@ -775,6 +777,17 @@ problem. It has the following attributes/sub-elements:
 
     *Default*: None
 
+
+``<use_windowed_multipole>`` Element
+------------------------------------
+
+The ``<use_windowed_multipole>`` element toggles the windowed multipole
+capability on or off. If this element is set to "True" and the relevant data is
+available, OpenMC will use the windowed multipole method to evaluate and Doppler
+broaden cross sections in the resolved resonance range.
+
+  *Default*: False
+
 ``<verbosity>`` Element
 -----------------------
 

openmc/settings.py

@@ -125,6 +125,9 @@ class SettingsFile(object):
         Coordinates of the lower-left point of the UFS mesh
     ufs_upper_right : tuple or list
         Coordinates of the upper-right point of the UFS mesh
+    use_windowed_multipole : bool
+        Whether or not windowed multipole can be used to evaluate resolved
+        resonance cross sections.
 
     """
 
@@ -201,6 +204,7 @@ class SettingsFile(object):
         self._settings_file = ET.Element("settings")
         self._run_mode_subelement = None
         self._source_element = None
+        self._multipole_active = None
 
     @property
     def run_mode(self):
@@ -386,6 +390,10 @@ class SettingsFile(object):
     def dd_count_interactions(self):
         return self._dd_count_interactions
 
+    @property
+    def use_windowed_multipole(self):
+        return self._multipole_active
+
     @run_mode.setter
     def run_mode(self, run_mode):
         if 'run_mode' not in ['eigenvalue', 'fixed source']:
@@ -750,6 +758,11 @@ class SettingsFile(object):
 
         self._dd_count_interactions = interactions
 
+    @use_windowed_multipole.setter
+    def use_windowed_multipole(self, active):
+        check_type('use_windowed_multipole', active, bool)
+        self._multipole_active = active
+
     def _create_run_mode_subelement(self):
 
         if self.run_mode == 'eigenvalue':
@@ -1024,6 +1037,12 @@ class SettingsFile(object):
             subelement = ET.SubElement(element, "count_interactions")
             subelement.text = str(self._dd_count_interactions).lower()
 
+    def _create_use_multipole_subelement(self):
+        if self._multipole_active is not None:
+            element = ET.SubElement(self._settings_file,
+                                    "use_windowed_multipole")
+            element.text = str(self._multipole_active)
+
     def export_to_xml(self):
         """Create a settings.xml file that can be used for a simulation.
 
@@ -1059,6 +1078,7 @@ class SettingsFile(object):
         self._create_track_subelement()
         self._create_ufs_subelement()
         self._create_dd_subelement()
+        self._create_use_multipole_subelement()
 
         # Clean the indentation in the file to be user-readable
         clean_xml_indentation(self._settings_file)

src/ace.F90

@@ -114,7 +114,7 @@ contains
           end if
 
           ! Read multipole file into the appropriate entry on the nuclides array
-          call read_multipole_data(i_nuclide)
+          if (multipole_active) call read_multipole_data(i_nuclide)
 
           ! Add name and alias to dictionary
           call already_read % add(name)

src/ace_header.F90

@@ -112,7 +112,7 @@ module ace_header
     type(UrrData), pointer :: urr_data => null()
 
     ! Multipole data
-    logical                           :: mp_present
+    logical                           :: mp_present = .false.
     type(MultipoleArray), allocatable :: multipole
 
     ! Reactions

src/global.F90

@@ -91,6 +91,9 @@ module global
   ! What to assume for expanding natural elements
   integer :: default_expand = ENDF_BVII1
 
+  ! Whether or not windowed multipole cross sections should be used.
+  logical :: multipole_active = .false.
+
   ! ============================================================================
   ! TALLY-RELATED VARIABLES
 

src/input_xml.F90

@@ -1054,6 +1054,20 @@ contains
       end select
     end if
 
+    ! Check to see if windowed multipole functionality is requested
+    if (check_for_node(doc, "use_windowed_multipole")) then
+      call get_node_value(doc, "use_windowed_multipole", temp_str)
+      select case (to_lower(temp_str))
+      case ('true', 't', '1', 'y')
+        multipole_active = .true.
+      case ('false', 'f', '0', 'n')
+        multipole_active = .false.
+      case default
+        call fatal_error("Unrecognized value for <use_windowed_multipole> in &
+             &settings.xml")
+      end select
+    end if
+
     ! Close settings XML file
     call close_xmldoc(doc)
 

src/relaxng/settings.rnc

@@ -162,5 +162,7 @@ element settings {
       (element E_max { xsd:double } |
         attribute E_max { xsd:double })?
     }*
-  }?
+  }? &
+
+  element use_windowed_multipole { xsd:boolean }?
 }

src/relaxng/settings.rng

@@ -738,5 +738,10 @@
         </zeroOrMore>
       </element>
     </optional>
+    <optional>
+      <element name="use_windowed_multipole">
+        <data type="boolean"/>
+      </element>
+    </optional>
   </interleave>
 </element>

tests/test_multipole/inputs_true.dat

@@ -1 +1 @@
-5c1cec635da5c4c869bdf58f62924a4cb1648e4ddecf0ce71b823cf45178767ba7f2e089b76d36e8616b1b21ffa43b32ab1b17d20bb74120f900b9e3e9ab9bcc
+7658bebe2b6f93feae06417a05bfd4bbbfca668eebd100d976543326439b82d16ea23752ac0537284e1839d9681714df116828daf30857bc83e86cc67e4550d7

tests/test_multipole/test_multipole.py

@@ -86,6 +86,7 @@ class DistribmatTestHarness(PyAPITestHarness):
         sets_file.particles = 1000
         sets_file.source = Source(space=Box([-1, -1, -1], [1, 1, 1]))
         sets_file.output = {'summary': True}
+        sets_file.use_windowed_multipole=True
         sets_file.export_to_xml()