From: Michael Orlitzky <michael@orlitzky.com>
Date: Tue, 25 Jun 2019 03:10:37 +0000 (-0400)
Subject: eja/euclidean_jordan_algebra.py: fix the rank of the spin factor algebra.
X-Git-Url: https://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=e45009fd88b842e5b881b21f6b6d42af57374ab9;p=sage.d.git

eja/euclidean_jordan_algebra.py: fix the rank of the spin factor algebra.
---

diff --git a/mjo/eja/euclidean_jordan_algebra.py b/mjo/eja/euclidean_jordan_algebra.py
index 849243c..1f03768 100644
--- a/mjo/eja/euclidean_jordan_algebra.py
+++ b/mjo/eja/euclidean_jordan_algebra.py
@@ -317,4 +317,8 @@ def eja_ln(dimension, field=QQ):
         Qi[0,0] = Qi[0,0] * ~field(2)
         Qs.append(Qi)
 
-    return FiniteDimensionalEuclideanJordanAlgebra(field,Qs,rank=2)
+    # The rank of the spin factor algebra is two, UNLESS we're in a
+    # one-dimensional ambient space (the rank is bounded by the
+    # ambient dimension).
+    rank = min(dimension,2)
+    return FiniteDimensionalEuclideanJordanAlgebra(field,Qs,rank=rank)