From: Michael Orlitzky <michael@orlitzky.com>
Date: Sat, 21 Nov 2020 02:30:51 +0000 (-0500)
Subject: eja: add a comment about sub-subalgebra representations.
X-Git-Url: https://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=09e103320c85de7be6846be6980642d37a5ca6a9;p=sage.d.git

eja: add a comment about sub-subalgebra representations.
---

diff --git a/mjo/eja/eja_subalgebra.py b/mjo/eja/eja_subalgebra.py
index 8f00373..85ada07 100644
--- a/mjo/eja/eja_subalgebra.py
+++ b/mjo/eja/eja_subalgebra.py
@@ -153,7 +153,11 @@ class FiniteDimensionalEuclideanJordanSubalgebra(FiniteDimensionalEuclideanJorda
         superalgebra_basis = [ self._superalgebra.from_vector(b)
                                for b in basis_vectors ]
 
+        # If our superalgebra is a subalgebra of something else, then
+        # these vectors won't have the right coordinates for
+        # V.span_of_basis() unless we use V.from_vector() on them.
         W = V.span_of_basis( V.from_vector(v) for v in basis_vectors )
+
         n = len(superalgebra_basis)
         mult_table = [[W.zero() for i in range(n)] for j in range(n)]
         for i in range(n):