From f85dc9dc9b52f38d151e82cd5bdcb9475a66c250 Mon Sep 17 00:00:00 2001
From: Ethan Peterson <ethan.peterson@mit.edu>
Date: Thu, 10 Mar 2022 13:35:41 -0500
Subject: [PATCH] adding helper method for EnergyFilter creation

---
 openmc/filter.py | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/openmc/filter.py b/openmc/filter.py
index df06d713f..be3d97679 100644
--- a/openmc/filter.py
+++ b/openmc/filter.py
@@ -1324,6 +1324,20 @@ class EnergyFilter(RealFilter):
             cv.check_greater_than('filter value', v0, 0., equality=True)
             cv.check_greater_than('filter value', v1, 0., equality=True)
 
+    @classmethod
+    def from_group_structure(cls, group_structure):
+        """Construct an EnergyFilter instance from a standard group structure.
+
+        Parameters
+        ----------
+        group_structure : str
+            Name of the group structure. Must be a valid key of
+            openmc.mgxs.GROUP_STRUCTURES dictionary.
+
+        """
+
+        return cls(openmc.mgxs.GROUP_STRUCTURES[group_structure.upper()])
+
 
 class EnergyoutFilter(EnergyFilter):
     """Bins tally events based on outgoing particle energy.