From 0a4a1e7e81b32b41bc837eb769a5da5c57fd6ce0 Mon Sep 17 00:00:00 2001
From: liangjg <liangjg2008@gmail.com>
Date: Sat, 29 Dec 2018 09:01:09 -0500
Subject: [PATCH] do not differentiate material by default

---
 openmc/deplete/operator.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/openmc/deplete/operator.py b/openmc/deplete/operator.py
index 37fbdd5e25..754e22f7d9 100644
--- a/openmc/deplete/operator.py
+++ b/openmc/deplete/operator.py
@@ -109,7 +109,7 @@ class Operator(TransportOperator):
 
     """
     def __init__(self, geometry, settings, chain_file=None, prev_results=None,
-                 diff_burnable_mats=True):
+                 diff_burnable_mats=False):
         super().__init__(chain_file)
         self.round_number = False
         self.settings = settings