X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=blobdiff_plain;f=mjo%2Feja%2FTODO;h=f4b9515c4ed643bd1f9a13c6fc0d6cefa3d32879;hp=e925c162786ab4da9bb7155ec8086cda0da05464;hb=HEAD;hpb=4c19598e53d8dd21c1cf92351fea2951db8e9cf4 diff --git a/mjo/eja/TODO b/mjo/eja/TODO index e925c16..b0d5378 100644 --- a/mjo/eja/TODO +++ b/mjo/eja/TODO @@ -1,25 +1,20 @@ -1. Add cartesian products to random_eja(). +1. Add references and start citing them. -2. Add references and start citing them. +2. Profile (and fix?) any remaining slow operations. -3. Implement the octonion simple EJA. +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. Pre-cache charpoly for some small algebras? +4. Add dimension bounds on any tests over AA that compute element + subalgebras. -RealSymmetricEJA(4): +5. The rational_algebra() stuff doesn't really belong in classes that + don't derive from RationalBasisEJA or its as-yet-nonexistent + element class. -sage: F = J.base_ring() -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]*X[7] + (F(2).sqrt()/2)*X[1]*X[5]*X[6]*X[7] + (1/4)*X[3]**2*X[7]**2 - (1/2)*X[0]*X[5]*X[7]**2 + (F(2).sqrt()/2)*X[2]*X[3]*X[6]*X[8] - (1/2)*X[1]*X[4]*X[6*X[8] - (1/2)*X[1]*X[3]*X[7]*X[8] + (F(2).sqrt()/2)*X[0]*X[4]*X[7]*X[8] + (1/4)*X[1]**2*X[8]**2 - (1/2)*X[0]*X[2]*X[8]**2 - (1/2)*X[2]*X[3]**2*X[9] + (F(2).sqrt()/2)*X[1]*X[3]*X[4]*X[9] - (1/2)*X[0]*X[4]**2*X[9] - (1/2)*X[1]**2*X[5]*X[9] + X[0]*X[2]*X[5]*X[9] - -5. Profile the construction of "large" matrix algebras (like the - 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. - -7. Set check_axioms=False for element-subalgebras outside of once or - twice in the test suite. +6. Add special det/trace method overrides for the algebras where we + know them? The only reason this might be tricky is because the + obvious solution is to subclass EJAElement, but then we might + collide with e.g. the Cartesian product element subclass.