X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=blobdiff_plain;f=mjo%2Feja%2FTODO;h=45a9ac06bf2c86020dee102143393e486fa408c5;hp=0d6edf2500664bbbad54e08b18f9e304765a7b6f;hb=cf5e64b70869df65c7bb38888de54b1083e60d45;hpb=f904a86173b5f0dab18a409407e8ac708d9efb4b diff --git a/mjo/eja/TODO b/mjo/eja/TODO index 0d6edf2..45a9ac0 100644 --- a/mjo/eja/TODO +++ b/mjo/eja/TODO @@ -1,22 +1,22 @@ -1. Add cartesian products to random_eja(). +1. Add references and start citing them. -2. Add references and start citing them. +2. Pre-cache charpoly for some more algebras. -3. Implement the octonion simple EJA. +3. Profile the construction of "large" matrix algebras (like the + 15-dimensional QuaternionHermitianAlgebra(3)) to find out why + they're so slow. -4. Pre-cache charpoly for some small algebras? +4. What the ever-loving fuck is this shit? -RealSymmetricEJA(4): + sage: O = Octonions(QQ) + sage: e0 = O.monomial(0) + sage: e0*[[[[]]]] + [[[[]]]]*e0 -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. Every once in a long while, the test -5. Profile the construction of "large" matrix algebras (like the - 15-dimensional QuaternionHermitianAlgebra(3)) to find out why - they're so slow. + sage: set_random_seed() + sage: x = random_eja().random_element() + sage: x.is_invertible() == (x.det() != 0) -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. + in eja_element.py returns False.