Merge pull request #518 from idaholab/mat_optimize

Optimize Material Update Pointers

.github/workflows/main.yml

@@ -160,6 +160,7 @@ jobs:
       - run: python benchmark/benchmark_big_model.py  
         name: Benchmark against big model
 
+
   changelog-test:
     runs-on: ubuntu-latest
     if: github.ref != 'refs/heads/main'

benchmark/benchmark_big_model.py

@@ -3,7 +3,7 @@
 import time
 import tracemalloc
 
-FAIL_THRESHOLD = 500
+FAIL_THRESHOLD = 30
 
 tracemalloc.start()
 start = time.time()

doc/source/changelog.rst

@@ -1,6 +1,13 @@
 MontePy Changelog
 =================
 
+#Next Version#
+--------------
+
+**Performance Improvement**
+
+* Fixed method of linking ``Material`` to ``ThermalScattering`` objects, avoiding a very expensive O(N:sup:`2`) (:issue:`510`).
+
 0.4.0
 --------------
 

montepy/data_inputs/data_input.py

@@ -179,6 +179,8 @@ def update_pointers(self, data_inputs):
 
         :param data_inputs: a list of the data inputs in the problem
         :type data_inputs: list
+        :returns: True iff this input should be removed from ``problem.data_inputs``
+        :rtype: bool, None
         """
         pass
 

montepy/data_inputs/material.py

@@ -177,18 +177,7 @@ def update_pointers(self, data_inputs):
         :param data_inputs: a list of the data inputs in the problem
         :type data_inputs: list
         """
-        for input in list(data_inputs):
-            if isinstance(input, thermal_scattering.ThermalScatteringLaw):
-                if input.old_number == self.number:
-                    if not self._thermal_scattering:
-                        self._thermal_scattering = input
-                        input._parent_material = self
-                        data_inputs.remove(input)
-                    else:
-                        raise MalformedInputError(
-                            self,
-                            f"Multiple MT inputs were specified for this material: {self.number}.",
-                        )
+        pass
 
     @staticmethod
     def _class_prefix():

montepy/data_inputs/thermal_scattering.py

@@ -122,19 +122,40 @@ def update_pointers(self, data_inputs):
 
         :param data_inputs: a list of the data inputs in the problem
         :type data_inputs: list
+        :returns: True iff this input should be removed from ``problem.data_inputs``
+        :rtype: bool
         """
+        # use caching first
+        if self._problem:
+            try:
+                mat = self._problem.materials[self.old_number]
+            except KeyError:
+                raise MalformedInputError(
+                    self._input, "MT input is detached from a parent material"
+                )
+        # brute force it
         found = False
-        for input in data_inputs:
-            if isinstance(input, montepy.data_inputs.material.Material):
-                if input.number == self.old_number:
+        for data_input in data_inputs:
+            if isinstance(data_input, montepy.data_inputs.material.Material):
+                if data_input.number == self.old_number:
+                    mat = data_input
                     found = True
-                    self._parent_material = input
-
+                    break
+        # actually update things
         if not found:
             raise MalformedInputError(
                 self._input, "MT input is detached from a parent material"
             )
 
+        if mat.thermal_scattering:
+            raise MalformedInputError(
+                self,
+                f"Multiple MT inputs were specified for this material: {self.old_number}.",
+            )
+        mat.thermal_scattering = self
+        self._parent_material = mat
+        return True
+
     def __str__(self):
         return f"THERMAL SCATTER: {self.thermal_scattering_laws}"
 

montepy/mcnp_problem.py

@@ -332,9 +332,11 @@ def handle_error(e):
                 ParticleTypeNotInCell,
             ) as e:
                 handle_error(e)
-        for input in self._data_inputs:
+        to_delete = []
+        for data_index, data_input in enumerate(self._data_inputs):
             try:
-                input.update_pointers(self._data_inputs)
+                if data_input.update_pointers(self._data_inputs):
+                    to_delete.append(data_index)
             except (
                 BrokenObjectLinkError,
                 MalformedInputError,
@@ -343,6 +345,8 @@ def handle_error(e):
             ) as e:
                 handle_error(e)
                 continue
+        for delete_index in to_delete[::-1]:
+            del self._data_inputs[delete_index]
 
     def remove_duplicate_surfaces(self, tolerance):
         """Finds duplicate surfaces in the problem, and remove them.

prof/dump_results.py

@@ -2,5 +2,5 @@
 from pstats import SortKey
 
 stats = pstats.Stats("prof/combined.prof")
-stats.sort_stats(SortKey.CUMULATIVE, SortKey.TIME).print_stats(300, "montepy")
-stats.sort_stats(SortKey.CUMULATIVE, SortKey.TIME).print_stats(100, "sly")
+stats.sort_stats(SortKey.CUMULATIVE, SortKey.TIME).print_stats("montepy", 50)
+stats.sort_stats(SortKey.CUMULATIVE, SortKey.TIME).print_stats("sly", 20)

prof/profile_big_model.py

@@ -10,6 +10,6 @@
 
 stats = pstats.Stats("prof/big.prof")
 stats.sort_stats(pstats.SortKey.CUMULATIVE, pstats.SortKey.TIME).print_stats(
-    100, "montepy"
+    "montepy", 70
 )
-stats.sort_stats(pstats.SortKey.CUMULATIVE, pstats.SortKey.TIME).print_stats(100, "sly")
+stats.sort_stats(pstats.SortKey.CUMULATIVE, pstats.SortKey.TIME).print_stats("sly", 20)

tests/test_material.py

@@ -340,7 +340,8 @@ def test_thermal_scattering_format_mcnp(self):
         in_str = "M20 1001.80c 0.5 8016.80c 0.5"
         input_card = Input([in_str], BlockType.DATA)
         material = Material(input_card)
-        material.update_pointers([card])
+        material.thermal_scattering = card
+        card._parent_material = material
         material.thermal_scattering.thermal_scattering_laws = ["grph.20t"]
         self.assertEqual(card.format_for_mcnp_input((6, 2, 0)), ["Mt20 grph.20t "])