Function propagate_symplectic 

pub fn propagate_symplectic(
    initial: &PropState,
    mu: Mu,
    dt: f64,
    duration: f64,
) -> SymplecticResult

Propagate a ballistic (thrust-free) orbit using the Störmer-Verlet symplectic integrator.

Returns the full trajectory. For ballistic orbits only — thrust is not supported because symplectic integrators lose their conservation guarantees with non-conservative forces.

Arguments

• initial — Initial state
• mu — Central body gravitational parameter
• dt — Fixed timestep (seconds)
• duration — Total propagation time (seconds)