From: Michael Orlitzky Date: Thu, 26 Nov 2020 02:59:28 +0000 (-0500) Subject: eja: start adding precomputed charpoly coeffs to the TODO. X-Git-Url: http://gitweb.michael.orlitzky.com/?p=sage.d.git;a=commitdiff_plain;h=3bbd8df6759e00a29a2df95a1479ea16e24bc3dc eja: start adding precomputed charpoly coeffs to the TODO. --- diff --git a/mjo/eja/TODO b/mjo/eja/TODO index f0901ca..fa05841 100644 --- a/mjo/eja/TODO +++ b/mjo/eja/TODO @@ -32,6 +32,11 @@ 8. Pre-cache charpoly for some small algebras? +RealSymmetricEJA(4): + +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] + 9. Compute the scalar in the general natural_inner_product() for matrices, so no overrides are necessary.