X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo%2Feja%2Feja_subalgebra.py;h=646da2fb8b649c11baa226833085c26564d75d46;hb=259d256fb765350eb6691efe1765c9f4e2a121bd;hp=e39792a91732724b5fc7bc8b352e8fd977c80940;hpb=6d30ad670e205bcfd299835ca67d93d7e1bfc2ec;p=sage.d.git

diff --git a/mjo/eja/eja_subalgebra.py b/mjo/eja/eja_subalgebra.py
index e39792a..646da2f 100644
--- a/mjo/eja/eja_subalgebra.py
+++ b/mjo/eja/eja_subalgebra.py
@@ -313,6 +313,18 @@ class FiniteDimensionalEuclideanJordanElementSubalgebra(FiniteDimensionalEuclide
             return self.monomial(self.one_basis())
 
 
+    def natural_basis_space(self):
+        """
+        Return the natural basis space of this algebra, which is identical
+        to that of its superalgebra.
+
+        This is correct "by definition," and avoids a mismatch when the
+        subalgebra is trivial (with no natural basis to infer anything
+        from) and the parent is not.
+        """
+        return self.superalgebra().natural_basis_space()
+
+
     def superalgebra(self):
         """
         Return the superalgebra that this algebra was generated from.
@@ -330,20 +342,20 @@ class FiniteDimensionalEuclideanJordanElementSubalgebra(FiniteDimensionalEuclide
         EXAMPLES::
 
             sage: J = RealSymmetricEJA(3)
-            sage: x = sum( i*J.gens()[i] for i in range(6) )
+            sage: x = J.monomial(0) + 2*J.monomial(2) + 5*J.monomial(5)
             sage: K = FiniteDimensionalEuclideanJordanElementSubalgebra(x)
             sage: K.vector_space()
-            Vector space of degree 6 and dimension 3 over Rational Field
+            Vector space of degree 6 and dimension 3 over...
             User basis matrix:
             [ 1  0  1  0  0  1]
-            [ 0  1  2  3  4  5]
-            [10 14 21 19 31 50]
+            [ 1  0  2  0  0  5]
+            [ 1  0  4  0  0 25]
             sage: (x^0).to_vector()
             (1, 0, 1, 0, 0, 1)
             sage: (x^1).to_vector()
-            (0, 1, 2, 3, 4, 5)
+            (1, 0, 2, 0, 0, 5)
             sage: (x^2).to_vector()
-            (10, 14, 21, 19, 31, 50)
+            (1, 0, 4, 0, 0, 25)
 
         """
         return self._vector_space