diagonalClass(beta)
Given a symmetric bilinear form, this method calls the congruenceDiagonalize command in order to produce a diagonal symmetric bilinear form isomorphic to $\beta$, with reduced square classes appearing as the diagonal entries.



Note that the GrothendieckWittClass type caches diagonal versions of a form once they've been computed. We can recover this quickly in the following way.

The object diagonalClass is a method function.