On Apr 14, 2009, at 5:35 PM, Maurizio wrote:
> > Hi all. > > I'm willing to invest some of my time to understand if I can be able > to do a step ahead with symbolic functions. > > How are special symbolic functions supposed to be defined? I am > willing to experiment with delta of dirac function. This has some > special properties (see http://en.wikipedia.org/wiki/Dirac_delta_function > ), some of them are really useful but I don't know how to define them > in a CAS like maxima or SAGE. > > I'm aware that it is already present in maxima, even though I don't > think it is recognized by SAGE. I am wondering whether a viable > approach could be to add to calculus.py a section similar to the one > of Function_gamma, so that SAGE simply interfaces to maxima. I don't > know if this is useful or not. > > Otherwise, I would be interested in knowing if this could be done with > the new symbolic package. Burcin proved to be very helpful in showing > me a simple way to define delta function by means of its values and he > assigned it as being the derivative of heaviside function (defined in > a sort of piecewise function): > > sage: heaviside(x).diff(x) > dirac(x) > The derivative of the dirac delta shows up in solid mechanics, is that defined at all? I have major problems with Maple because its integration of Heaviside functions is often wrong. Cheers, Tim. --- Tim Lahey PhD Candidate, Systems Design Engineering University of Waterloo http://www.linkedin.com/in/timlahey --~--~---------~--~----~------------~-------~--~----~ 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 URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---