ConvexRationalPolyhedralCone: Make __and__ an alias for intersection

Author: Matthias Koeppe

src/sage/geometry/cone.py

@@ -3017,6 +3017,13 @@ def intersection(self, other):
             N( 2, 5)
             in 2-d lattice N
 
+        The intersection can also be expressed using the operator ``&``::
+
+            sage: (cone1 & cone2).rays()
+            N(-1, 3),
+            N( 2, 5)
+            in 2-d lattice N
+
         It is OK to intersect cones living in sublattices of the same ambient
         lattice::
 
@@ -3058,6 +3065,8 @@ def intersection(self, other):
         p.add_constraints(other._PPL_cone().constraints())
         return _Cone_from_PPL(p, self.lattice().intersection(other.lattice()))
 
+    __and__ = intersection
+
     def is_equivalent(self, other):
         r"""
         Check if ``self`` is "mathematically" the same as ``other``.