Changeset 6592:93e31b24782e for sage/rings/polynomial/multi_polynomial_ring_generic.pyx

Timestamp:

10/04/07 10:11:55 (6 years ago)

Author:

William Stein <wstein@…>

Branch:

default

Message:

merge in Martin Albrecht's #816.

File:

• sage/rings/polynomial/multi_polynomial_ring_generic.pyx (modified) (1 diff)

sage/rings/polynomial/multi_polynomial_ring_generic.pyx

@@ -480 +480 @@
         d = dict( zip(tuple(exponents), coeffs) ) 
         return self(multi_polynomial_element.MPolynomial_polydict(self, PolyDict(d)))
-        
+
+    def new_ring(self, names=None, order=None):
+        """
+        Return a new multivariate polynomial ring which isomorphic to
+        self, but has a different ordering given by the parameter
+        'order' or names given by the parameter 'names'.
+
+        INPUT:
+            order -- a term order
+
+        EXAMPLE:
+            sage: P.<x,y,z> = PolynomialRing(GF(127),3,order='lex')
+            sage: x > y^2
+            True
+            sage: Q.<x,y,z> = P.new_ring(order='degrevlex')
+            sage: x > y^2
+            False
+        """
+        base_ring = self.base_ring()
+        if names is None:
+            names = self.variable_names()
+        if order is None:
+            order = self.term_order()
+        
+        from polynomial_ring_constructor import PolynomialRing
+        return PolynomialRing(base_ring, self.ngens(), names, order=order)
         
 ####################