The following all works
sage: a = sqrt(2)*sqrt(3)*sqrt(6)
sage: v = vector([a])
sage: M = Matrix([v, v])
sage: a.canonicalize_radical()
6
sage: v.canonicalize_radical()
(6)
However the following doesn't work:
sage: M = Matrix([v, v])
sage: M.canonicalize_radical()
Could I request, as a feature, the "vectorization" of canonicalize_radical for matrices?