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Homework Help: Python, RungeKutta and first-order differential equation system.

  1. Dec 13, 2008 #1

    2. Relevant equations

    The equation is, given to me by lurflurf,:
    mv' + f(v ) + s(u) = F(t), t > 0, u(0) = U0, v (0) = V0
    where v=u'
    For the record the equation was:
    mu'' + f(u' ) + s(u) = F(t), t > 0, u(0) = U0, u' (0) = V0 .

    3. The attempt at a solution

    Code (Text):
     def rhs(u, t):
        return [u[1],
                (1./m)*(external(t) - friction(u[1]) - spring(u[0]))]
    This is the solution, but I don't get how yuu go from the equation to rhs.
    Can someone help me?
  2. jcsd
  3. Dec 13, 2008 #2
    Re: Python, RukgeKutta and first-order differential equation system.

    Here is the page with the exercises: http://www.ifi.uio.no/~inf1100/ODE_project.pdf" [Broken]

    The equation is given in 11.36 and it is 11.37 I need help with.
    The solution is http://www.ifi.uio.no/~inf1100/live-programming/oscillator_v1.py" [Broken]

    ODESolver http://www.ifi.uio.no/~inf1100/src/oo/ODESolver.py" [Broken]

    Scitools contains array, plot etc
    Last edited by a moderator: May 3, 2017
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