Module lattice_qcd_rs::simulation::monte_carlo::metropolis_hastings

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Expand description

Metropolis Hastings method

I recommend not using method in this module, but they may have niche usage. look at super::metropolis_hastings_sweep for a more common algorithm.

Example

use lattice_qcd_rs::{
    error::ImplementationError,
    simulation::monte_carlo::MetropolisHastingsDeltaDiagnostic,
    simulation::state::{LatticeState, LatticeStateDefault},
    ComplexField,
};

let mut rng = rand::thread_rng();

let size = 1_000_f64;
let number_of_pts = 4;
let beta = 2_f64;
let mut simulation =
    LatticeStateDefault::<4>::new_determinist(size, beta, number_of_pts, &mut rng)?;

let spread_parameter = 1E-5_f64;
let mut mc = MetropolisHastingsDeltaDiagnostic::new(spread_parameter, rng)
    .ok_or(ImplementationError::OptionWithUnexpectedNone)?;

let number_of_sims = 100;
for _ in 0..number_of_sims / 10 {
    for _ in 0..10 {
        simulation = simulation.monte_carlo_step(&mut mc)?;
    }
    simulation.normalize_link_matrices(); // we renormalize all matrices back to SU(3);
}
let average = simulation
    .average_trace_plaquette()
    .ok_or(ImplementationError::OptionWithUnexpectedNone)?
    .real();

Structs