eja: add another TODO item.

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

diff --git a/mjo/eja/TODO b/mjo/eja/TODO
index e8a2a8d4fc8988b1ad6f744a69daba9cf0582397..b27f2f12875e317fd2b088a74d7395c84ab8e454 100644 (file)
--- a/mjo/eja/TODO
+++ b/mjo/eja/TODO
@@ -11,3 +11,22 @@
    DirectSumEJA.
 
 6. Switch to QQ in *all* algebras for _charpoly_coefficients().
+   This only works when we know that the basis can be rationalized...
+   which is the case at least for the concrete EJAs we provide,
+   but not in general.
+
+7. Pass already_echelonized (default: False) and echelon_basis
+   (default: None) into the subalgebra constructor. The value of
+   already_echelonized can be passed to V.span_of_basis() to save
+   some time, and usinf e.g. FreeModule_submodule_with_basis_field
+   we may somehow be able to pass the echelon basis straight in to
+   save time.
+
+   This may require supporting "basis" as a list of basis vectors
+   (as opposed to superalgebra elements) in the subalgebra constructor.
+
+8. Implement random_instance() for general algebras as random_eja().
+   Copy/paste the "general" construction into the other classes that
+   can use it. The general construction can be something like "call
+   random_instance() on something that inherits me and return the
+   result."