On Jul 24, 7:32 am, William Stein <wst...@gmail.com> wrote: > On Fri, Jul 23, 2010 at 2:27 PM, KvS <keesvansch...@gmail.com> wrote: > > Dear all, > > > I'm sorry if this is a 'utfs' question, but I couldn't really find a > > clear answer. I would like to do some numerical operations on a Sage > > function (/expression) provided by the user (i.e. typed in the > > notebook). Ideally I would like to have this function available as a > > Cython function to perform these operations (assuming say the input is > > a composition of only 'elementary' functions). So say the user enters > > 'f(x)=x^2' I would like to have a Cython function like > > > cdef f_ cython(double x): > > return x**2 > > > so that I can run other Cython functions that evaluate f_cython (a > > lot). Is there a standard way to do something like this? If not, I > > guess I could try producing the code for the Cython function > > definition as a string and then call eval(...) on it or something like > > that? What would be the best way, keeping an eye on optimisation for > > speed? > > > Many thanks, Kees > > You might look at fast_callable and fast_float, which are in Sage. > Often Cython only beats them by a factor of 2, and they are very easy > to use. > > William > > -- > William Stein > Professor of Mathematics > University of Washingtonhttp://wstein.org
Thanks William. I'll compare your suggestion with Cython for some typical cases to get an idea of the speed differences. Cheers, Kees -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
