From: Michael Orlitzky <michael@orlitzky.com>
Date: Sat, 5 Dec 2020 03:28:19 +0000 (-0500)
Subject: eja: reimplement multiplication_table() without member variables.
X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=commitdiff_plain;h=795ac83cd78143e36d47fa267fe6ddf1ca8da111

eja: reimplement multiplication_table() without member variables.
---

diff --git a/mjo/eja/eja_algebra.py b/mjo/eja/eja_algebra.py
index 3d49005..3b13ce1 100644
--- a/mjo/eja/eja_algebra.py
+++ b/mjo/eja/eja_algebra.py
@@ -614,20 +614,15 @@ class FiniteDimensionalEuclideanJordanAlgebra(CombinatorialFreeModule):
 
         """
         n = self.dimension()
-        M = [ [ self.zero() for j in range(n) ]
-              for i in range(n) ]
-        for i in range(n):
-            for j in range(i+1):
-                M[i][j] = self._multiplication_table[i][j]
-                M[j][i] = M[i][j]
+        # Prepend the header row.
+        M = [["*"] + list(self.gens())]
 
-        for i in range(n):
-            # Prepend the left "header" column entry Can't do this in
-            # the loop because it messes up the symmetry.
-            M[i] = [self.monomial(i)] + M[i]
+        # And to each subsequent row, prepend an entry that belongs to
+        # the left-side "header column."
+        M += [ [self.monomial(i)] + [ self.product_on_basis(i,j)
+                                      for j in range(n) ]
+               for i in range(n) ]
 
-        # Prepend the header row.
-        M = [["*"] + list(self.gens())] + M
         return table(M, header_row=True, header_column=True, frame=True)