From: Michael Orlitzky <michael@orlitzky.com>
Date: Thu, 29 Aug 2019 13:44:07 +0000 (-0400)
Subject: eja: convert back the the starting field after quaternion embedding.
X-Git-Url: https://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=f420787bd1cc7bfb467d31b5a1581e985434fb31;p=sage.d.git

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 4504362..d1658c2 100644
--- 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):