On 1/4/07, Joshua Kantor <[EMAIL PROTECTED]> wrote: > > In response to Williams sage-2.0 plan I wanted to describe what I had done > with using gsl to implement a numerical ode solver. I believe that the > patch containing this will be applied after > doing a recent pull or upgrade but I'm not sure(is this true?). If not
...... > > Ideas for extension: > > 1. It would be nice if there was some facility for automatically > converting a nth order ODE > to a system of first order ones. If an n-th order ODE is simply a function of the variables x, y0=y, y1=y',...,yn = y^(n), then this is easy to write. Should the n-th order ODEs form a class? > > 2. It would be nice if there was some facility for automatically computing > the jacobian when the functions involved are rational functions and > elementary functions. Maxima has a function called hessian, as well as a determinant. Together, I think they should do what you want. > > > 3. Numerically computing the jacobian: For the algorithms that require the > jacobian It would be possible to numerically compute the jacobian, > however I was wary of doing this by default. Does anyone have any knowledge > about > the benefits of this, can it cause instability (using the numerical > jacobian > instead of the exact one). I don't but I agree with you anyway. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
