From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 4 Nov 2020 15:14:34 +0000 (-0500)
Subject: eja: remove more vestigial charpoly stuff.
X-Git-Url: http://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=884b2015690a50a12f99852ea82c399309164f22;p=sage.d.git

eja: remove more vestigial charpoly stuff.
---

diff --git a/mjo/eja/eja_algebra.py b/mjo/eja/eja_algebra.py
index 2b769ac..fc64510 100644
--- a/mjo/eja/eja_algebra.py
+++ b/mjo/eja/eja_algebra.py
@@ -235,66 +235,6 @@ class FiniteDimensionalEuclideanJordanAlgebra(CombinatorialFreeModule):
     def product_on_basis(self, i, j):
         return self._multiplication_table[i][j]
 
-    def _a_regular_element(self):
-        """
-        Guess a regular element. Needed to compute the basis for our
-        characteristic polynomial coefficients.
-
-        SETUP::
-
-            sage: from mjo.eja.eja_algebra import random_eja
-
-        TESTS:
-
-        Ensure that this hacky method succeeds for every algebra that we
-        know how to construct::
-
-            sage: set_random_seed()
-            sage: J = random_eja()
-            sage: J._a_regular_element().is_regular()
-            True
-
-        """
-        gs = self.gens()
-        z = self.sum( (i+1)*gs[i] for i in range(len(gs)) )
-        if not z.is_regular():
-            raise ValueError("don't know a regular element")
-        return z
-
-
-    @cached_method
-    def _charpoly_basis_space(self):
-        """
-        Return the vector space spanned by the basis used in our
-        characteristic polynomial coefficients. This is used not only to
-        compute those coefficients, but also any time we need to
-        evaluate the coefficients (like when we compute the trace or
-        determinant).
-        """
-        z = self._a_regular_element()
-        # Don't use the parent vector space directly here in case this
-        # happens to be a subalgebra. In that case, we would be e.g.
-        # two-dimensional but span_of_basis() would expect three
-        # coordinates.
-        V = VectorSpace(self.base_ring(), self.vector_space().dimension())
-        basis = [ (z**k).to_vector() for k in range(self.rank()) ]
-        V1 = V.span_of_basis( basis )
-        b =  (V1.basis() + V1.complement().basis())
-        return V.span_of_basis(b)
-
-
-    def _charpoly_coeff(self, i):
-        """
-        Return the coefficient polynomial "a_{i}" of this algebra's
-        general characteristic polynomial.
-
-        Having this be a separate cached method lets us compute and
-        store the trace/determinant (a_{r-1} and a_{0} respectively)
-        separate from the entire characteristic polynomial.
-        """
-        return self._charpoly_coefficients()[i]
-
-
     @cached_method
     def characteristic_polynomial(self):
         """