def construct_circuit(self, x, qr=None, inverse=False):
"""
Construct the first order expansion based on given data.
Args:
x (numpy.ndarray): 1-D to-be-transformed data.
qr (QauntumRegister): the QuantumRegister object for the circuit, if None,
generate new registers with name q.
inverse (bool): whether or not inverse the circuit
Returns:
QuantumCircuit: a quantum circuit transform data x.
"""
if not isinstance(x, np.ndarray):
raise TypeError("x should be numpy array.")
if x.ndim != 1:
raise ValueError("x should be 1-D array.")
if x.shape[0] != self._num_qubits:
raise ValueError(
"number of qubits and data dimension must be the same.")
if qr is None:
QuantumRegister(self._num_qubits, 'q')
qc = QuantumCircuit(qr)
composite_gate = self._build_composite_gate(x, qr)
qc._attach(composite_gate if inverse ==
False else composite_gate.inverse())
return qc
circuit = QuantumCircuit(quantum_r, classical_r)
circuit.h(quantum_r[0])
circuit.rx(0, quantum_r[0])
circuit.cx(quantum_r[0], quantum_r[1])
circuit.cx(quantum_r[0], quantum_r[1])
circuit.h(quantum_r[0])
circuit.cx(quantum_r[0], quantum_r[1])
composite_gate_1 = CompositeGate("composite1", [],
[quantum_r[x] for x in range(4)])
composite_gate_1._attach(CnotGate(quantum_r[0], quantum_r[1]))
circuit._attach(composite_gate_1)
circuit.h(quantum_r[0])
composite_gate_2 = CompositeGate("composite2", [],
[quantum_r[x] for x in range(4)])
composite_gate_2._attach(CnotGate(quantum_r[0], quantum_r[1]))
circuit._attach(composite_gate_2)
circuit.cx(quantum_r[0], quantum_r[1])
circuit.h(quantum_r[0])
composite_gate_3 = CompositeGate("composite3", [],
[quantum_r[x] for x in range(4)])
composite_gate_3._attach(CnotGate(quantum_r[0], quantum_r[1]))
composite_gate_3._attach(CnotGate(quantum_r[0], quantum_r[2]))
