Refine quotient ring category to Fields()

when it is isomorphic to a field
sagemath · Nov 30, 2016 · ca050d3 · ca050d3
1 parent 1a3cb94
commit ca050d3
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/src/sage/rings/polynomial/polynomial_quotient_ring.py b/src/sage/rings/polynomial/polynomial_quotient_ring.py
@@ -813,7 +813,11 @@ def is_field(self, proof = True):
             sage: S.is_field()
             True
         """
-        return self.base_ring().is_field(proof) and self.modulus().is_irreducible()
+        ret = self.base_ring().is_field(proof) and self.modulus().is_irreducible()
+        if ret:
+            from sage.categories.all import Fields
+            self._refine_category_(Fields())
+        return ret
 
     def krull_dimension(self):
         return self.base_ring().krull_dimension()