X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo%2Feja%2FTODO;h=94fb172aba0dda1d601e7c70ccf4f991749a6fcc;hb=f02d09e53017ba3b3b5592a45be84487c580379d;hp=87a162c73ab3ccf86623496dee39064e8b96bfb7;hpb=2a3ec0787b28bc35b3624594d921a995c9425d3a;p=sage.d.git diff --git a/mjo/eja/TODO b/mjo/eja/TODO index 87a162c..94fb172 100644 --- a/mjo/eja/TODO +++ b/mjo/eja/TODO @@ -4,17 +4,14 @@ 3. Implement the octonion simple EJA. -4. Factor out the unit-norm basis (and operator symmetry) tests once - all of the algebras pass. +4. Override random_instance(), one(), et cetera in DirectSumEJA. -5. Override random_instance(), one(), et cetera in DirectSumEJA. - -6. Switch to QQ in *all* algebras for _charpoly_coefficients(). +5. 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 +6. 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 @@ -24,8 +21,11 @@ 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." +7. The inner product should be an *argument* to the main EJA + constructor. Afterwards, the basis normalization step should be + optional (and enabled by default) for ALL algebras, since any + algebra can have a nonstandard inner-product and its basis can be + normalized with respect to that inner- product. For example, the + HadamardEJA could be equipped with an inner- product that is twice + the usual one. Then for the basis to be orthonormal, we would need + to divide e.g. (1,0,0) by <(1,0,0),(1,0,0)> = 2 to normalize it.