Struct Circuit 

pub struct Circuit { /* private fields */ }

A quantum circuit: an ordered list of Ops over n qubits and some number of classical bits.

Gate methods take plain usize indices, return &mut Self, and so chain fluently. They record operations without validating eagerly; call Circuit::validate (which backends do automatically) to check all indices at once.

Examples

use everett::prelude::*;

let mut c = Circuit::new(3);
c.h(0).cnot(0, 1).cnot(1, 2); // a 3-qubit GHZ circuit
assert_eq!(c.len(), 3);

Implementations

impl Circuit

pub fn new(num_qubits: usize) -> Self

Creates an empty circuit over num_qubits qubits and no classical bits.

pub fn with_classical(num_qubits: usize, num_classical: usize) -> Self

Creates an empty circuit with both a quantum and a classical register.

pub fn num_qubits(&self) -> usize

The number of qubits.

pub fn num_classical(&self) -> usize

The number of classical bits.

pub fn ops(&self) -> &[Op]

The recorded operations.

pub fn len(&self) -> usize

The number of operations.

pub fn is_empty(&self) -> bool

Whether the circuit has no operations.

pub fn gate1(&mut self, gate: Gate1, target: usize) -> &mut Self

Appends an arbitrary single-qubit gate on target.

pub fn gate2(&mut self, gate: Gate2, a: usize, b: usize) -> &mut Self

Appends an arbitrary two-qubit gate on operands a and b.

pub fn controlled( &mut self, controls: &[usize], gate: Gate1, target: usize, ) -> &mut Self

Appends a single-qubit gate on target, controlled on all of controls.

pub fn compose(&mut self, sub: &Circuit) -> &mut Self

Appends another circuit’s operations into this one, in place. Useful for inlining a subroutine such as a width-k QFT.

The sub-circuit’s qubit and classical indices are used as-is, so they must fit within this circuit’s registers (checked by Self::validate).

pub fn h(&mut self, q: usize) -> &mut Self

Appends a Hadamard on q.

pub fn x(&mut self, q: usize) -> &mut Self

Appends a Pauli-X on q.

pub fn y(&mut self, q: usize) -> &mut Self

Appends a Pauli-Y on q.

pub fn z(&mut self, q: usize) -> &mut Self

Appends a Pauli-Z on q.

pub fn s(&mut self, q: usize) -> &mut Self

Appends an S gate on q.

pub fn t(&mut self, q: usize) -> &mut Self

Appends a T gate on q.

pub fn rx(&mut self, q: usize, theta: f64) -> &mut Self

Appends an X-rotation by theta on q.

pub fn ry(&mut self, q: usize, theta: f64) -> &mut Self

Appends a Y-rotation by theta on q.

pub fn rz(&mut self, q: usize, theta: f64) -> &mut Self

Appends a Z-rotation by theta on q.

pub fn phase(&mut self, q: usize, lambda: f64) -> &mut Self

Appends a relative phase e^{i*lambda} on q.

pub fn cnot(&mut self, control: usize, target: usize) -> &mut Self

Appends a CNOT with control and target.

pub fn cz(&mut self, a: usize, b: usize) -> &mut Self

Appends a controlled-Z on a and b (symmetric).

pub fn swap(&mut self, a: usize, b: usize) -> &mut Self

Appends a SWAP of a and b.

pub fn measure(&mut self, qubit: usize, into: usize) -> &mut Self

Measures qubit, storing the outcome in classical bit into.

pub fn x_if(&mut self, bit: usize, q: usize) -> &mut Self

Applies a Pauli-X on q if classical bit bit is set. The basic feed-forward correction used by teleportation.

pub fn z_if(&mut self, bit: usize, q: usize) -> &mut Self

Applies a Pauli-Z on q if classical bit bit is set.

pub fn if_classic(&mut self, bit: usize, op: Op) -> &mut Self

Runs op only if classical bit is set. General classical control.

pub fn validate(&self) -> Result<()>

Checks that every qubit and classical-bit index is in range and that no multi-qubit gate names the same qubit twice.

Errors

Returns the first Error found, or Ok(()) if the circuit is valid.

pub fn to_qasm(&self) -> Result<String>

Emits a valid OpenQASM 3.0 string for this circuit.

Errors

Returns Error::Qasm if any gate has no OpenQASM 3 name.

pub fn from_qasm(src: &str) -> Result<Self>

Parses an OpenQASM 3.0 string into a Circuit.

Errors

Returns Error::Qasm on any parse error.

Trait Implementations

impl Clone for Circuit

fn clone(&self) -> Circuit

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Circuit

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

Formats the value using the given formatter.

impl PartialEq for Circuit

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Circuit