Struct ReducedDensityMatrix 

pub struct ReducedDensityMatrix {
    pub qubits: Vec<usize>,
    pub data: Vec<Complex64>,
    pub metadata: RunMetadata,
}

Reduced density matrix of a qubit subset, returned by Simulate::reduced_density_matrix.

Fields

qubits: Vec<usize>

The subsystem as it was requested, which fixes the index order below.

data: Vec<Complex64>

Row major with side 2^k over k = qubits.len(): data[t * 2^k + t'] is <t|rho|t'>, where bit i of t is the state of qubits[i], so qubits[0] is the lowest bit as q[0] is in a basis index. Trace one, Hermitian to rounding.

metadata: RunMetadata

Implementations

impl ReducedDensityMatrix

pub fn purity(&self) -> f64

Tr(rho^2): 1 for a pure marginal, 2^-k for the maximally mixed one.

Trait Implementations

impl Clone for ReducedDensityMatrix

fn clone(&self) -> ReducedDensityMatrix

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ReducedDensityMatrix

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

Formats the value using the given formatter.