Struct HamiltonianSystem 

pub struct HamiltonianSystem {
    pub q: Vec<f64>,
    pub p: Vec<f64>,
    pub dt: f64,
    pub time: f64,
}

A complete Hamiltonian system with state (q, p) and a user-supplied Hamiltonian gradient function.

Uses symplectic Euler integration by default for long-time stability.

Fields

q: Vec<f64>

Generalised coordinates q.

p: Vec<f64>

Conjugate momenta p.

dt: f64

Time step.

time: f64

Current simulation time.

Implementations

impl HamiltonianSystem

pub fn new(q: Vec<f64>, p: Vec<f64>, dt: f64) -> Self

Create a new system with given initial conditions and time step.

pub fn step(&mut self, grad_h: &dyn Fn(&[f64], &[f64]) -> (Vec<f64>, Vec<f64>))

Advance one time step using symplectic Euler integration.

grad_h(q, p) must return (∂H/∂p, ∂H/∂q).

pub fn run( &mut self, n: usize, grad_h: &dyn Fn(&[f64], &[f64]) -> (Vec<f64>, Vec<f64>), ) -> (Vec<Vec<f64>>, Vec<Vec<f64>>)

Run n steps and return the trajectory as (q_history, p_history).

pub fn kinetic_energy(&self, masses: &[f64]) -> f64

Evaluate a scalar Hamiltonian H(q,p) = Σ p_i²/(2m_i) + V(q). Provided for convenience; grad_h must still be supplied externally.

Trait Implementations

impl Clone for HamiltonianSystem

fn clone(&self) -> HamiltonianSystem

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for HamiltonianSystem

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.