Struct StateVector 

pub struct StateVector {
    pub n_qubits: u8,
    pub amps: Vec<Amp>,
}

A reconstructed fixed-point state vector — the hashed quantity.

Fields

n_qubits: u8

amps: Vec<Amp>

Implementations

impl StateVector

pub fn basis(n: u8, k: usize) -> StateVector

The |k⟩ computational basis state on n qubits.

pub fn canonical_bytes(&self) -> Vec<u8>

Canonical serialization of the amplitudes: re_le(i64) ‖ im_le(i64) per amplitude, in index order — the bytes the statevector hash covers.

pub fn statevector_hash(&self) -> [u8; 32]

statevector-equivalence — the portable BLAKE3 identity of the whole reconstructed vector. Two conforming sinks agree on this iff every amplitude is byte-identical, on every machine, with no tolerance parameter.

Examples found in repository

examples/bell.rs (line 28)

fn main() {
    let mut c = Circuit::new(2);
    c.h(0).cx(0, 1); // a Bell pair

    let sv = c.simulate().expect("simulate");

    println!("circuit    {} qubits, {} gates", c.n_qubits, c.ops.len());
    let (backend, why) = qt::recommend_backend(&c);
    println!("backend    {backend:?} — {why}");

    println!("outcomes");
    for (state, p) in qt::top_outcomes(&sv, 4) {
        if p > 0.0 {
            println!("  |{state:02b}>  {p:.6}");
        }
    }

    // Not "a hash of this run" — the reconstruction is byte-exact, so this is the
    // same value natively, in a browser, and in a WASI component at the edge.
    let h = sv.statevector_hash();
    print!("state-hash ");
    for b in h {
        print!("{b:02x}");
    }
    println!();
}

pub fn prob_weights(&self) -> Vec<i128>

Per-basis-state probability weights |amp|^2 at scale 2^(2·FRAC), i128 (un-normalized; summing gives ≈ 2^(2·FRAC)). No divide — the sampler walks these directly.

pub fn sample_shots(&self, seed: u64, shots: u64) -> Vec<u64>

Sample shots computational-basis measurements with the pinned splitmix64 seeded by seed; returns a per-basis-state count vector. Deterministic on every machine.

pub fn histogram_hash(&self, seed: u64, shots: u64) -> [u8; 32]

shot-histogram-equivalence — the portable BLAKE3 identity of a shot histogram at a pinned (seed, shots).

pub fn fidelity_fx(&self, other: &StateVector) -> i64

State fidelity |⟨self|other⟩|^2 in the fixed-point floor (result at 2^FRAC) — the quantum-information-theoretic similarity metric. For two exactly-reconstructed vectors it is a diagnostic (identical states give ≈ ONE); it is the metric a future float/behavioral quantum prior — which cannot back intent=replicate — would conform against. i128 accumulation so the overlap sum never overflows.

Trait Implementations

impl Clone for StateVector

fn clone(&self) -> StateVector

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StateVector

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

Formats the value using the given formatter.

impl Eq for StateVector

impl PartialEq for StateVector

fn eq(&self, other: &StateVector) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for StateVector