Qx.Export.OpenQASM (Qx - Quantum Computing Simulator v0.5.0)

Export Qx quantum circuits to OpenQASM format.

This module provides functionality to convert Qx quantum circuits into OpenQASM code that can be executed on real quantum hardware platforms including:

IBM Quantum (IBM Q)
AWS Braket
Google Cirq (via OpenQASM import)
Rigetti (via AWS Braket)
IonQ (via AWS Braket or Azure Quantum)

Supports both OpenQASM 2.0 and 3.0 specifications.

OpenQASM Versions

OpenQASM 2.0: Legacy version, widely supported, no conditional operations
OpenQASM 3.0: Modern version with conditionals, mid-circuit measurements, and control flow

Supported Features

Single-qubit gates (H, X, Y, Z, S, T, RX, RY, RZ, Phase)
Multi-qubit gates (CNOT/CX, CZ, Toffoli/CCX)
Measurements and classical bits
Conditional operations (OpenQASM 3.0 only)
Barriers for visualization organization

Examples

# Export a Bell state circuit to OpenQASM 3.0
circuit = Qx.circuit(2)
  |> Qx.h(0)
  |> Qx.cnot(0, 1)
  |> Qx.measure(0, 0)
  |> Qx.measure(1, 1)

qasm = Qx.Export.OpenQASM.to_qasm(circuit)
File.write!("bell_state.qasm", qasm)

# Export to OpenQASM 2.0 (no conditionals)
qasm2 = Qx.Export.OpenQASM.to_qasm(circuit, version: 2)

# Export with custom options
qasm = Qx.Export.OpenQASM.to_qasm(circuit,
  version: 3,
  include_comments: true,
  gate_style: :verbose
)

Platform Compatibility

Platform	Version	Mid-circuit Measurement	Conditionals
IBM Quantum	2.0, 3.0	3.0 only	3.0 only
AWS Braket	3.0	Yes	Yes
Google Cirq	2.0	No	No
Rigetti	2.0, 3.0	3.0 only	3.0 only

Limitations

Circuits with conditionals cannot be exported to OpenQASM 2.0
Custom gate definitions are expanded to standard gates
Qubit ordering follows MSB convention (qubit 0 is leftmost)

Summary

Functions

to_qasm(circuit, options \\ [])

Converts a Qx quantum circuit to OpenQASM format.

Functions

to_qasm(circuit, options \\ [])

Converts a Qx quantum circuit to OpenQASM format.

Parameters

circuit - A Qx.QuantumCircuit struct
options - Keyword list of options (default: [])

Options

:version - OpenQASM version (2 or 3, default: 3)
:include_comments - Add descriptive comments (default: false)
:gate_style - Gate naming style (:standard or :verbose, default: :standard)

Returns

A string containing the OpenQASM program.

Raises

Qx.GateError - If circuit contains unsupported gates
Qx.ConditionalError - If circuit has conditionals but version is 2
ArgumentError - If invalid options are provided

Examples

circuit = Qx.circuit(2) |> Qx.h(0) |> Qx.cnot(0, 1)
qasm = Qx.Export.OpenQASM.to_qasm(circuit)

# Output:
# OPENQASM 3.0;
# include "stdgates.inc";
#
# qubit[2] q;
# bit[2] c;
#
# h q[0];
# cx q[0], q[1];