Merge pull request #841 from digvijay-y/performance

Improve NumberedObjectCollection.check_number

Author: MicahGale

doc/source/changelog.rst

@@ -8,6 +8,9 @@ MontePy Changelog
 #Next Version#
 --------------
 
+**Performance Improvement**
+
+* Optimized :math:`\mathcal{O}(N^2)` scaling in :func:`montepy.NumberedObjectCollection.request_number` by improving ``NumberedObjectCollection.check_number`` to :math:`\mathcal{O}(N)` (:issue:`786`). 
 
 **Features Added**
 

montepy/numbered_object_collection.py

@@ -244,7 +244,6 @@ def check_number(self, number):
         """
         if not isinstance(number, Integral):
             raise TypeError("The number must be an int")
-
         if number < 0:
             raise ValueError(f"The number must be non-negative. {number} given.")
         conflict = False
@@ -635,14 +634,16 @@ def request_number(self, start_num=None, step=None):
         If starting_number, or step are not specified :func:`starting_number`,
         and :func:`step` are used as default values.
 
-
         .. versionchanged:: 0.5.0
             In 0.5.0 the default values were changed to reference :func:`starting_number` and :func:`step`.
 
+        .. versionchanged:: 1.2.0
+            start_num is now only a suggestion for the starting point. The returned number is not guaranteed to be start_num, but will be the next available number after start_num (or after the last assigned number).
+
         Parameters
         ----------
         start_num : int
-            the starting number to check.
+            Suggested starting number to check. Not guaranteed to be the returned value.
         step : int
             the increment to jump by to find new numbers.
 
@@ -659,13 +660,21 @@ def request_number(self, start_num=None, step=None):
             start_num = self.starting_number
         if step is None:
             step = self.step
-        number = start_num
+        try:
+            self.check_number(start_num)
+            return start_num
+        except NumberConflictError:
+            pass
+        # Increment to next available number. If not set use start_num as is
+        last_assigned = getattr(self, "_last_assigned_number", start_num - step) + step
+        number = max(start_num, last_assigned)
         while True:
             try:
                 self.check_number(number)
                 break
             except NumberConflictError:
                 number += step
+        self._last_assigned_number = number
         return number
 
     def next_number(self, step=1):