eja: work towards fixing element subalgebras.

[sage.d.git] / mjo / eja / eja_element_subalgebra.py

diff --git a/mjo/eja/eja_element_subalgebra.py b/mjo/eja/eja_element_subalgebra.py
index 846c13b095cb812edff5c3340c1f0cc8337fe149..ee8e0c67db2773537aefc04d82ee58b7a0b4cca0 100644 (file)
--- a/mjo/eja/eja_element_subalgebra.py
+++ b/mjo/eja/eja_element_subalgebra.py
@@ -14,32 +14,10 @@ class FiniteDimensionalEJAElementSubalgebra(FiniteDimensionalEJASubalgebra):
         # and continually rref() it until the rank stops going
         # up. When n=10 but the dimension of the algebra is 1, that
         # can save a shitload of time (especially over AA).
-        powers = tuple( elt**k for k in range(superalgebra.dimension()) )
-        power_vectors = ( p.to_vector() for p in powers )
-        P = matrix(superalgebra.base_ring(), power_vectors)
-
-        # Echelonize the matrix ourselves, because otherwise the
-        # call to P.pivot_rows() below can choose a non-optimal
-        # row-reduction algorithm. In particular, scaling can
-        # help over AA because it avoids the RecursionError that
-        # gets thrown when we have to look too hard for a root.
-        #
-        # Beware: QQ supports an entirely different set of "algorithm"
-        # keywords than do AA and RR.
-        algo = None
-        if superalgebra.base_ring() is not QQ:
-            algo = "scaled_partial_pivoting"
-            P.echelonize(algorithm=algo)
-
-            # Figure out which powers form a linearly-independent set.
-            ind_rows = P.pivot_rows()
-
-            # Pick those out of the list of all powers.
-            basis = tuple(map(powers.__getitem__, ind_rows))
-
+        powers = tuple( elt**k for k in range(elt.degree()) )
 
         super().__init__(superalgebra,
-                         basis,
+                         powers,
                          associative=True,
                          **kwargs)