X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=blobdiff_plain;f=mjo%2Feja%2FTODO;h=13b00ac6a3056eaf623ac5c2905be6c7d049706c;hp=70e945ed4bbe499bd6dde2a92c0153e30f1dede0;hb=db1f7761ebf564221669137ae07476ea45d82a2c;hpb=f7c62e76aa3ec8837094e68686554d372c94b16f diff --git a/mjo/eja/TODO b/mjo/eja/TODO index 70e945e..13b00ac 100644 --- a/mjo/eja/TODO +++ b/mjo/eja/TODO @@ -2,7 +2,8 @@ 2. Add references and start citing them. -3. Implement the octonion simple EJA. +3. Implement the octonion simple EJA. We don't actually need octonions + for this to work, only their real embedding (some 8x8 monstrosity). 4. Pre-cache charpoly for some small algebras? @@ -15,12 +16,22 @@ sage: a0 = (1/4)*X[4]**2*X[6]**2 - (1/2)*X[2]*X[5]*X[6]**2 - (1/2)*X[3]*X[4]*X[6 15-dimensional QuaternionHermitianAlgebra(3)) to find out why they're so slow. -6. We should compute whether or not the algebra is associative if it - is unknown. I guess the "associative" argument should be ternary - (True, False, None)? We should also figure out the correct - True/False values for the example classes, and of course add an - _is_associative() method. +6. Instead of storing a basis multiplication matrix, just make + product_on_basis() a cached method and manually cache its + entries. The cython cached method lookup should be faster than a + python-based matrix lookup anyway. -7. When field=RDF, subalgebra construction is failing because the - inner product isn't associative? Actually, it's the combination - of field=RDF and orthonormalize=True. +7. What the ever-loving fuck is this shit? + + sage: O = Octonions(QQ) + sage: e0 = O.monomial(0) + sage: e0*[[[[]]]] + [[[[]]]]*e0 + +8. In fact, could my octonion matrix algebra be generalized for any + algebra of matrices over the reals whose entries are not real? Then + we wouldn't need real embeddings at all. They might even be fricking + vector spaces if I did that... + +9. Add HurwitzMatrixAlgebra subclass between MatrixAlgebra and + OctonionMatrixAlgebra.