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use crate::{
StabilizerCHForm,
circuit::{CliffordCircuit, CliffordGate},
error::Result,
types::pauli::{Pauli, PauliString},
};
impl StabilizerCHForm {
/// Applies the Hadamard gate to the qubit at index `qarg`.
///
/// Time complexity: O(n^2)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the Hadamard gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_h(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_h(qarg)
}
/// Applies the Pauli-X gate to the qubit at index `qarg`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the Pauli-X gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_x(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_x(qarg)
}
/// Applies the Pauli-Y gate to the qubit at index `qarg`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the Pauli-Y gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_y(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_y(qarg)
}
/// Applies the Pauli-Z gate to the qubit at index `qarg`.
///
/// Time complexity: O(1)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the Pauli-Z gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_z(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_z(qarg)
}
/// Applies the Phase (S) gate to the qubit at index `qarg`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the Phase (S) gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_s(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_s(qarg)
}
/// Applies the adjoint Phase (S†) gate to the qubit at index `qarg`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the adjoint Phase (S†) gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_sdg(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_sdg(qarg)
}
/// Applies the √X gate to the qubit at index `qarg`.
///
/// Time complexity: O(n^2)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the √X gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_sqrt_x(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_sqrt_x(qarg)
}
/// Applies the adjoint of the √X gate to the qubit at index `qarg`.
///
/// Time complexity: O(n^2)
///
/// ## Arguments
/// * `qarg` - The index of the qubit to which the adjoint of the √X gate is applied.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_sqrt_xdg(&mut self, qarg: usize) -> Result<()> {
self.left_multiply_sqrt_xdg(qarg)
}
/// Applies the CNOT (CX) gate with control qubit at index `control` and target qubit at index `target`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `control` - The index of the control qubit.
/// * `target` - The index of the target qubit.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_cx(&mut self, control: usize, target: usize) -> Result<()> {
self.left_multiply_cx(control, target)
}
/// Applies the CZ gate between qubits at indices `qarg1` and `qarg2`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `qarg1` - The index of the first qubit.
/// * `qarg2` - The index of the second qubit.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_cz(&mut self, qarg1: usize, qarg2: usize) -> Result<()> {
self.left_multiply_cz(qarg1, qarg2)
}
/// Applies the SWAP gate between the qubits at indices `qarg1` and `qarg2`.
///
/// Time complexity: O(n)
///
/// ## Arguments
/// * `qarg1` - The index of the first qubit.
/// * `qarg2` - The index of the second qubit.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_swap(&mut self, qarg1: usize, qarg2: usize) -> Result<()> {
self.left_multiply_swap(qarg1, qarg2)
}
/// Applies a Clifford gate to the stabilizer state.
////
/// ## Arguments
/// * `gate` - The Clifford gate to apply.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_gate(&mut self, gate: &CliffordGate) -> Result<()> {
match gate {
CliffordGate::H(qarg) => self.apply_h(*qarg)?,
CliffordGate::X(qarg) => self.apply_x(*qarg)?,
CliffordGate::Y(qarg) => self.apply_y(*qarg)?,
CliffordGate::Z(qarg) => self.apply_z(*qarg)?,
CliffordGate::S(qarg) => self.apply_s(*qarg)?,
CliffordGate::Sdg(qarg) => self.apply_sdg(*qarg)?,
CliffordGate::SqrtX(qarg) => self.apply_sqrt_x(*qarg)?,
CliffordGate::SqrtXdg(qarg) => self.apply_sqrt_xdg(*qarg)?,
CliffordGate::CX(control, target) => self.apply_cx(*control, *target)?,
CliffordGate::CZ(control, target) => self.apply_cz(*control, *target)?,
CliffordGate::Swap(q1, q2) => self.apply_swap(*q1, *q2)?,
}
Ok(())
}
/// Applies a Pauli string to the stabilizer state.
///
/// ## Arguments
/// * `pauli_string` - The Pauli string to apply.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_pauli(&mut self, pauli_string: &PauliString) -> Result<()> {
match pauli_string {
PauliString::Dense(ops) => {
for (qubit, &op) in ops.iter().enumerate() {
match op {
Pauli::I => {}
Pauli::X => self.apply_x(qubit)?,
Pauli::Y => self.apply_y(qubit)?,
Pauli::Z => self.apply_z(qubit)?,
}
}
}
PauliString::Sparse(terms) => {
for term in terms {
match term.op {
Pauli::I => {}
Pauli::X => self.apply_x(term.qubit)?,
Pauli::Y => self.apply_y(term.qubit)?,
Pauli::Z => self.apply_z(term.qubit)?,
}
}
}
}
Ok(())
}
/// Applies a Clifford circuit to the stabilizer state.
///
/// ## Arguments
/// * `circuit` - The Clifford circuit to apply.
///
/// ## Returns
/// A [`Result`] indicating success or failure.
pub fn apply_circuit(&mut self, circuit: &CliffordCircuit) -> Result<()> {
for gate in &circuit.gates {
self.apply_gate(gate)?;
}
Ok(())
}
}