The methods you suggest essentially takes care of the mass matrix problem by solving a linear system numerically during numerical integration. I am familiar with tools out there that do this, but this isn't what I'm looking to do. I haven't seen one that is written directly usable in Python -- do you know of one? The netlib packages have this capability, but I'm no Fortran programmer.
What I am interested in doing is solving the linear system symbolically so that first order equations can be generated symbolically and the most generic of ODE solvers will work. This also eliminates the iteration that is being done by the ODE solver during time integration. Thanks, ~Luke On Sep 29, 8:07 pm, Tim Lahey <tim.la...@gmail.com> wrote: > On Sep 29, 2009, at 7:15 PM, Alan Bromborsky wrote: > > > Are there differential equation solvers where you don't have to invert > > the matrix? > > A Newmark-Beta scheme will directly solve a second-order system of ODEs. > The standard form uses iteration to solve the system so no inversion is > necessary. For linear second-order problems you can rewrite things to > use matrix algebra. > > For more information, I recommend Bathe and Wilson, > > Klaus-Jürgen Bathe and Edward L. Wilson. Numerical Methods in Finite > Element Analysis. Prentice Hall, Englewood Cliffs, New Jersey, > 1976. > > There are other second order solvers out there too. > > Cheers, > > Tim. > > --- > Tim Lahey > PhD Candidate, Systems Design Engineering > University of Waterloohttp://www.linkedin.com/in/timlahey --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---
