Struct DensityMatrix 

pub struct DensityMatrix {
    pub rho: Vec<Vec<Complex>>,
}

Density matrix for mixed states.

Fields

rho: Vec<Vec<Complex>>

Implementations

impl DensityMatrix

pub fn new(rho: Vec<Vec<Complex>>) -> Self

pub fn from_pure_state(psi: &[Complex]) -> Self

pub fn dim(&self) -> usize

pub fn trace(&self) -> Complex

pub fn purity(&self) -> f64

Purity: Tr(rho^2). 1 for pure states, 1/d for maximally mixed.

pub fn von_neumann_entropy(&self) -> f64

Von Neumann entropy: -Tr(rho * ln(rho)). Approximated using eigenvalues from diagonalization for 2x2, or using purity-based bound for larger systems.

Trait Implementations

impl Clone for DensityMatrix

fn clone(&self) -> DensityMatrix

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DensityMatrix

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

Formats the value using the given formatter.