On Mon, Jan 19, 2015 at 11:19 AM, Ondřej Čertík <ondrej.cer...@gmail.com> wrote: > Hi Vincent, > > On Sun, Jan 18, 2015 at 10:06 AM, Vincent Delecroix > <20100.delecr...@gmail.com> wrote: >> Hi, >> >> 2015-01-18 18:03 UTC+01:00, Ondřej Čertík <ondrej.cer...@gmail.com>: >>> Can you invent an example, that can't be converted to polynomials? >>> Perhaps (a1+a2+a3+sqrt(5)*a4+sqrt(3)*a5)^25? >> >> Still doable. You need to involve log, exp, cos or similar >> transcendental functions. > > Can you show me how to do that? I tried: > > sage: K.<sqrt3> = QuadraticField(3) > sage: K.<sqrt5> = QuadraticField(5) > sage: R.<a1,a2,a3,a4,a5> = K[] > sage: time f = (a1+a2+a3+sqrt5*a4+sqrt3*a5)^25 > > But I got: > > TypeError: unsupported operand parent(s) for '*': 'Number Field in > sqrt3 with defining polynomial x^2 - 3' and 'Multivariate Polynomial > Ring in a1, a2 > , a3, a4, a5 over Number Field in sqrt5 with defining polynomial x^2 - 5' > > Full stacktrace here: > > https://gist.github.com/certik/a7f2434820f8dbf890b9
I think I figured it out: sage: K.<sqrt3> = QuadraticField(3) sage: L.<sqrt5> = K.extension(x^2-5) sage: R.<a1,a2,a3,a4,a5> = L[] sage: time f = (a1+a2+a3+sqrt5*a4+sqrt3*a5)^18 CPU times: user 2.43 s, sys: 3.94 ms, total: 2.44 s Wall time: 2.44 s (I did smaller exponent so that it finishes.) Ondrej -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
