human
I wrote the below code

    def leapfrog(pos, vel, step):
        '\n                                Inside    loop    of    Scan.    Performs    one    step    of    leapfrog    update,    using\n                                Hamiltonian    dynamics.\n\n                                Parameters\n                                ----------\n                                pos:    theano    matrix\n                                                in    leapfrog    update    equations,    represents    pos(t),    position    at    time    t\n                                vel:    theano    matrix\n                                                in    leapfrog    update    equations,    represents    vel(t    -    stepsize/2),\n                                                velocity    at    time    (t    -    stepsize/2)\n                                step:    theano    scalar\n                                                scalar    value    controlling    amount    by    which    to    move\n\n                                Returns\n                                -------\n                                rval1:    [theano    matrix,    theano    matrix]\n                                                Symbolic    theano    matrices    for    new    position    pos(t    +    stepsize),    and\n                                                velocity    vel(t    +    stepsize/2)\n                                rval2:    dictionary\n                                                Dictionary    of    updates    for    the    Scan    Op\n                                '
        dE_dpos = TT.grad(energy_fn(pos).sum(), pos)
        new_vel = (vel - (step * dE_dpos))
        new_pos = (pos + (step * new_vel))
        return ([new_pos, new_vel], {})
    initial_energy = energy_fn(initial_pos)
    dE_dpos = TT.grad(initial_energy.sum(), initial_pos)
    vel_half_step = (initial_vel - ((0.5 * stepsize) * dE_dpos))
    pos_full_step = (initial_pos + (stepsize * vel_half_step))
    ((all_pos, all_vel), scan_updates) =...

What's a good function header?

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Here's a good function header?
assistant
#Here's a good function header.

def simulate_dynamics(initial_pos, initial_vel, stepsize, n_steps, energy_fn):