def test_pass_cx_cancellation_own_template(self):
"""
Check the cancellation of CX gates for the apply of a self made template cx-cx.
"""
qr = QuantumRegister(2, 'qr')
circuit_in = QuantumCircuit(qr)
circuit_in.h(qr[0])
circuit_in.h(qr[0])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[1], qr[0])
circuit_in.cx(qr[1], qr[0])
dag_in = circuit_to_dag(circuit_in)
qrt = QuantumRegister(2, 'qrc')
qct = QuantumCircuit(qrt)
qct.cx(0, 1)
qct.cx(0, 1)
template_list = [qct]
pass_ = TemplateOptimization(template_list)
dag_opt = pass_.run(dag_in)
circuit_expected = QuantumCircuit(qr)
circuit_expected.h(qr[0])
circuit_expected.h(qr[0])
dag_expected = circuit_to_dag(circuit_expected)
self.assertEqual(dag_opt, dag_expected)
def test_pass_cx_cancellation_template_from_library(self):
"""
Check the cancellation of CX gates for the apply of the library template cx-cx (2a_2).
"""
qr = QuantumRegister(2, 'qr')
circuit_in = QuantumCircuit(qr)
circuit_in.h(qr[0])
circuit_in.h(qr[0])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[0], qr[1])
circuit_in.cx(qr[1], qr[0])
circuit_in.cx(qr[1], qr[0])
dag_in = circuit_to_dag(circuit_in)
template_list = [template_nct_2a_2()]
pass_ = TemplateOptimization(template_list)
dag_opt = pass_.run(dag_in)
circuit_expected = QuantumCircuit(qr)
circuit_expected.h(qr[0])
circuit_expected.h(qr[0])
dag_expected = circuit_to_dag(circuit_expected)
self.assertEqual(dag_opt, dag_expected)
def test_pass_template_nct_5a(self):
"""
Verify the result of template matching and substitution with the template 5a_3.
q_0: ───────■─────────■────■──
┌─┴─┐ ┌─┴─┐ │
q_1: ──■──┤ X ├──■──┤ X ├──┼──
┌─┴─┐└───┘┌─┴─┐└───┘┌─┴─┐
q_2: ┤ X ├─────┤ X ├─────┤ X ├
└───┘ └───┘ └───┘
The circuit before optimization is:
┌───┐ ┌───┐
qr_0: ┤ X ├───────────────┤ X ├─────
└─┬─┘ ┌───┐┌───┐└─┬─┘
qr_1: ──┼────■──┤ X ├┤ Z ├──┼────■──
│ │ └─┬─┘└───┘ │ │
qr_2: ──┼────┼────■────■────■────┼──
│ │ ┌───┐┌─┴─┐ │ │
qr_3: ──■────┼──┤ H ├┤ X ├──■────┼──
│ ┌─┴─┐└───┘└───┘ ┌─┴─┐
qr_4: ──■──┤ X ├───────────────┤ X ├
└───┘ └───┘
The match is given by [0,1][1,2][2,7], after substitution the circuit becomes:
┌───┐ ┌───┐
qr_0: ┤ X ├───────────────┤ X ├
└─┬─┘ ┌───┐┌───┐└─┬─┘
qr_1: ──┼───────┤ X ├┤ Z ├──┼──
│ └─┬─┘└───┘ │
qr_2: ──┼────■────■────■────■──
│ │ ┌───┐┌─┴─┐ │
qr_3: ──■────┼──┤ H ├┤ X ├──■──
│ ┌─┴─┐└───┘└───┘
qr_4: ──■──┤ X ├───────────────
└───┘
"""
qr = QuantumRegister(5, 'qr')
circuit_in = QuantumCircuit(qr)
circuit_in.ccx(qr[3], qr[4], qr[0])
circuit_in.cx(qr[1], qr[4])
circuit_in.cx(qr[2], qr[1])
circuit_in.h(qr[3])
circuit_in.z(qr[1])
circuit_in.cx(qr[2], qr[3])
circuit_in.ccx(qr[2], qr[3], qr[0])
circuit_in.cx(qr[1], qr[4])
dag_in = circuit_to_dag(circuit_in)
template_list = [template_nct_5a_3()]
pass_ = TemplateOptimization(template_list)
dag_opt = pass_.run(dag_in)
circuit_expected = QuantumCircuit(qr)
circuit_expected.ccx(qr[3], qr[4], qr[0])
circuit_expected.cx(qr[2], qr[4])
circuit_expected.cx(qr[2], qr[1])
circuit_expected.z(qr[1])
circuit_expected.h(qr[3])
circuit_expected.cx(qr[2], qr[3])
circuit_expected.ccx(qr[2], qr[3], qr[0])
dag_expected = circuit_to_dag(circuit_expected)
self.assertEqual(dag_opt, dag_expected)