X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=blobdiff_plain;f=mjo%2Feja%2FTODO;h=f4b9515c4ed643bd1f9a13c6fc0d6cefa3d32879;hp=07c85b536fd8631ecd35fad3e6a161c84459d2cf;hb=HEAD;hpb=1bbade9f41ffbfe366b15d0db657f666bc1f025d diff --git a/mjo/eja/TODO b/mjo/eja/TODO index 07c85b5..b0d5378 100644 --- a/mjo/eja/TODO +++ b/mjo/eja/TODO @@ -1,33 +1,20 @@ 1. Add references and start citing them. -2. Pre-cache charpoly for some small algebras? +2. Profile (and fix?) any remaining slow operations. -RealSymmetricEJA(4): +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... -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] +4. Add dimension bounds on any tests over AA that compute element + subalgebras. -3. Profile the construction of "large" matrix algebras (like the - 15-dimensional QuaternionHermitianAlgebra(3)) to find out why - they're so slow. +5. The rational_algebra() stuff doesn't really belong in classes that + don't derive from RationalBasisEJA or its as-yet-nonexistent + element class. -4. 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. NOTE: we should still be able - to recompute the table somehow. Is this worth it? - -5. What the ever-loving fuck is this shit? - - sage: O = Octonions(QQ) - sage: e0 = O.monomial(0) - sage: e0*[[[[]]]] - [[[[]]]]*e0 - -7. Every once in a long while, the test - - sage: set_random_seed() - sage: x = random_eja().random_element() - sage: x.is_invertible() == (x.det() != 0) - - in eja_element.py returns False. +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.