Struct VqeOptimizer 

pub struct VqeOptimizer {
    pub hamiltonian: PauliHamiltonian,
    pub ansatz: HardwareEfficientAnsatz,
    pub init_params: Vec<f64>,
    pub max_iter: usize,
    pub tol: f64,
    pub learning_rate: f64,
}

VQE optimizer: minimizes ⟨ψ(θ)|H|ψ(θ)⟩ over ansatz parameters θ.

Fields

hamiltonian: PauliHamiltonian

The Hamiltonian to minimize

ansatz: HardwareEfficientAnsatz

The variational ansatz

init_params: Vec<f64>

Initial parameters

max_iter: usize

Maximum gradient-descent iterations

tol: f64

Convergence tolerance

learning_rate: f64

Learning rate for gradient descent

Implementations

impl VqeOptimizer

pub fn new( hamiltonian: PauliHamiltonian, ansatz: HardwareEfficientAnsatz, init_params: Vec<f64>, ) -> Self

Create a new VQE optimizer.

pub fn energy(&self, params: &[f64]) -> QcResult<f64>

Evaluate the energy ⟨H⟩ at the given parameters.

pub fn gradient(&self, params: &[f64]) -> QcResult<Vec<f64>>

Compute gradient using the parameter-shift rule.

∂E/∂θ_k = 0.5 * [E(θ_k + π/2) - E(θ_k - π/2)]

pub fn run(&mut self) -> QcResult<VqeResult>

Run VQE optimization using gradient descent with momentum.

Trait Implementations

impl Clone for VqeOptimizer

fn clone(&self) -> VqeOptimizer

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for VqeOptimizer

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

Formats the value using the given formatter.