eja: add a TODO for tomorrow.

[sage.d.git] / mjo / eja / TODO

diff --git a/mjo/eja/TODO b/mjo/eja/TODO
index 51c2a33b542569c431d986a0d165d8774b0d49eb..bb2b7f30069dda7ba5b1c63ec7062f1ab397c596 100644 (file)
--- a/mjo/eja/TODO
+++ b/mjo/eja/TODO
@@ -1,21 +1,17 @@
-1. Add CartesianProductEJA.
+1. Add references and start citing them.
 
-2. Check the axioms in the constructor when check != False?
+2. Profile (and fix?) any remaining slow operations.
 
-3. Add references and start citing them.
+3. When we take a Cartesian product involving a trivial algebra, we
+   could easily cache the identity and charpoly coefficients using
+   the nontrivial factor. On the other hand, it's nice that we can
+   test out some alternate code paths...
 
-4. Implement the octonion simple EJA.
+4. Can we hit "x" with the deortho matrix and delegate to the
+   _rational_algebra to speed up minimal_polynomial?
 
-5. Factor out the unit-norm basis (and operator symmetry) tests once
-   all of the algebras pass.
+5. In CartesianProductEJA we already know the multiplication table and
+   inner product matrix. Refactor things until it's no longer
+   necessary to duplicate that work.
 
-6. Implement spectral projector decomposition for EJA operators
-   using jordan_form() or eigenmatrix_right(). I suppose we can
-   ignore the problem of base rings for now and just let it crash
-   if we're not using AA as our base field.
-
-7. Do we really need to orthonormalize the basis in a subalgebra?
-   So long as we can decompose the operator (which is invariant
-   under changes of basis), who cares?
-
-8. Check that our field is a subring of RLF.
+6. Eliminate the matrix_space() override in CartesianProductEJA.