eja: convert back the the starting field after quaternion embedding.

We already do this for the complex simple EJA, and this un-breaks using
other fields.

diff --git a/mjo/eja/eja_algebra.py b/mjo/eja/eja_algebra.py
index 4504362a4f76c66112db8d47c00f8cd42711d305..d1658c2fba1aaf43e1115dee500bfd6b9c3602ac 100644 (file)
--- a/mjo/eja/eja_algebra.py
+++ b/mjo/eja/eja_algebra.py
@@ -1704,7 +1704,10 @@ class QuaternionHermitianEJA(QuaternionMatrixEuclideanJordanAlgebra,
                     S.append(Sij_J)
                     Sij_K = cls.real_embed(K*Eij - K*Eij.transpose())
                     S.append(Sij_K)
-        return S
+
+        # Since we embedded these, we can drop back to the "field" that we
+        # started with instead of the quaternion algebra "Q".
+        return ( s.change_ring(field) for s in S )
 
 
     def __init__(self, n, field=QQ, **kwargs):