Tim, On Mon, Apr 2, 2012 at 1:37 PM, Tim Lahey <[email protected]> wrote: > On Mon, Apr 2, 2012 at 4:23 PM, Luke <[email protected]> wrote: >> >> One reason to have a custom Lagrangian class is that it helps keep >> track of systems where you have a large number of >> particles/bodies/constraints/interacting forces. For simple systems >> you can surely write the Lagrangian in a line or two, but for more >> interesting systems, it becomes onerous and error prone to do this >> "manually". Having a class which allows you to pass it a list of >> particles/bodies, and the forces/torques acting on them, as well as >> any kinematic constraints that may be present, greatly simplifies the >> work the user must do and reduces the likelihood of making a mistake. >> I see many reasons to have a custom Lagrangian class. > > I can see a reason to have a class to hold the Lagrangian (i.e., the > work-energy expression), but the Euler-Lagrange equation itself should > be broken out separately since it has uses far beyond mechanics. I've > been thinking about writing support for general Calculus of Variations > in SymPy, but it's likely to wait until the end of the summer at the > earliest.
The Euler-Lagrange module I posted as a sympy issue already handles most Lagrangians. The only thing I did not include is constraints, but that should not be too diffcult to add. Cheers, Brian > Cheers, > > Tim. > > -- > Tim Lahey > PhD Candidate, Systems Design Engineering > University of Waterloo > http://about.me/tjlahey > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/sympy?hl=en. > -- Brian E. Granger Cal Poly State University, San Luis Obispo [email protected] and [email protected] -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
