Struct PauliRotation 

pub struct PauliRotation<const W: usize> {
    pub support: Vec<u32>,
    pub gen_x: [u64; W],
    pub gen_z: [u64; W],
    pub theta: f64,
}

A rotation U = exp(-i · θ · P / 2).

In the Heisenberg picture, conjugation by U either leaves the input invariant (if [input, P] = 0) or maps it to cos(θ) · input + sin(θ) · i · input · P. Hence MAX_FANOUT = 2.

Examples

use paulistrings::channel::PauliRotation;
use paulistrings::PauliString;

let gen = PauliString::<1>::z(0);
let rot = PauliRotation::<1> {
    support: vec![0],
    gen_x: gen.x,
    gen_z: gen.z,
    theta: std::f64::consts::FRAC_PI_4,
};

Fields

support: Vec<u32>

Qubits the generator P acts on (the channel’s support).

gen_x: [u64; W]

X-part of the generator P, restricted to support.

gen_z: [u64; W]

Z-part of the generator P, restricted to support.

theta: f64

Rotation angle in radians.

Trait Implementations

impl<const W: usize> Channel<W> for PauliRotation<W>

fn max_fanout(&self) -> usize

Maximum number of output terms produced per input term. Used by the engine to size the scratch buffer up-front.

fn support(&self) -> &[u32]

Qubits this channel acts on. Outputs differ from inputs only at these bit positions; the engine uses this for bucket layout (§5).

fn apply( &self, input_x: &[u64; W], input_z: &[u64; W], coeff: Complex64, out: &mut OutputBuffer<'_, W>, )

Apply the channel to a single input term, writing outputs to out.

fn apply_adjoint( &self, input_x: &[u64; W], input_z: &[u64; W], coeff: Complex64, out: &mut OutputBuffer<'_, W>, )

Apply the channel’s adjoint to a single input term, writing outputs to out. Used by the engine in Direction::Heisenberg mode for backpropagating observables.