change str to self.STR_RENDER in Expression.simplify

2014-12-23 10:07:36 +01:00
parent 5b4ef79982
commit 1f86b234ea
1 changed files with 1 additions and 1 deletions
--- a/pymath/expression.py
+++ b/pymath/expression.py
@@ -133,7 +133,7 @@ class Expression(object):
                if new_s != old_s:
                    old_s = new_s
                    yield new_s
-            if old_s != str(self.child):
+            if old_s != self.STR_RENDER([self.child]):
                yield self.STR_RENDER([self.child])