def main():
# parameters for generating random state: |psi>
alpha, beta, gamma = random.random(), random.random(), random.random()
# reference state: T|psi>
qs_expect = QState(1)
qs_expect.rz(0, phase=alpha).rx(0, phase=beta).rz(0, phase=gamma).t(0)
# prepare initial state
qs = QState(3)
qs.h(0).s(0) # |Y>
qs.h(1).t(1) # |A>
qs.rz(2, phase=alpha).rx(2, phase=beta).rz(2, phase=gamma) # |psi>
# T gate (only with X,Z,H,CNOT and measurement)
qs.cx(1, 2)
mval = qs.m(qid=[2]).last
if mval == '1':
qs.cx(1, 0).h(0).cx(1, 0).h(0)
qs.x(1).z(1)
qs_actual = qs.partial(qid=[1])
# show the result
print("== expect ==")
qs_expect.show()
print("== actual ==")
qs_actual.show()
print("== fidelity ==")
print("{:.6f}".format(qs_actual.fidelity(qs_expect)))
def test_partial_3_permutation(self):
"""test 'partial' (3-qubit permutation)
"""
qs_ini = QState(qubit_num=3).h(0).h(1).cx(1, 2)
qs = qs_ini.partial([2, 0, 1])
actual = qs.amp
expect = np.array([(0.5 + 0j), 0j, (0.5 + 0j), 0j, 0j, (0.5 + 0j), 0j,
(0.5 + 0j)])
ans = equal_vectors(actual, expect)
self.assertEqual(ans, True)
def test_partial_2_from_3(self):
"""test 'partial' (2-qubit state from 3-qubit)
"""
qs_ini = QState(qubit_num=3).h(0).h(1).cx(1, 2)
qs = qs_ini.partial([1, 2])
actual = qs.amp
expect = np.array([(0.7071067811865476 + 0j), 0j, 0j,
(0.7071067811865476 + 0j)])
ans = equal_vectors(actual, expect)
self.assertEqual(ans, True)
def logical_zero():
anc = [0, 1, 2, 3, 4, 5, 6] # registers for ancila
cod = [7, 8, 9, 10, 11, 12, 13] # registers for steane code
qs_total = QState(14)
# g1
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.cx(anc[0], cod[3]).cx(anc[1],
cod[4]).cx(anc[2],
cod[5]).cx(anc[3], cod[6])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': qs_total.z(cod[0]).z(cod[1]).z(cod[2]).z(cod[3])
qs_total.reset(qid=anc)
# g2
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.cx(anc[0], cod[1]).cx(anc[1],
cod[2]).cx(anc[2],
cod[5]).cx(anc[3], cod[6])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': qs_total.z(cod[0]).z(cod[1]).z(cod[4]).z(cod[5])
qs_total.reset(qid=anc)
# g3
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.cx(anc[0], cod[0]).cx(anc[1],
cod[2]).cx(anc[2],
cod[4]).cx(anc[3], cod[6])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': qs_total.z(cod[2]).z(cod[4]).z(cod[6])
qs_total.reset(qid=anc)
# g4
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.cz(anc[0], cod[3]).cz(anc[1],
cod[4]).cz(anc[2],
cod[5]).cz(anc[3], cod[6])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': qs_total.x(cod[0]).x(cod[1]).x(cod[2]).x(cod[3])
qs_total.reset(qid=anc)
# g5
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.cz(anc[0], cod[1]).cz(anc[1],
cod[2]).cz(anc[2],
cod[5]).cz(anc[3], cod[6])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': qs_total.x(cod[0]).x(cod[1]).x(cod[4]).x(cod[5])
qs_total.reset(qid=anc)
# g6
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.cz(anc[0], cod[0]).cz(anc[1],
cod[2]).cz(anc[2],
cod[4]).cz(anc[3], cod[6])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 4)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': qs_total.x(cod[2]).x(cod[4]).x(cod[6])
qs_total.reset(qid=anc)
# g7
qs_total.h(anc[0])
[qs_total.cx(anc[0], anc[i]) for i in range(1, 7)]
[qs_total.cz(anc[i], cod[i]) for i in range(7)]
[qs_total.cx(anc[0], anc[i]) for i in range(1, 7)]
qs_total.h(anc[0])
mval = qs_total.m(qid=[anc[0]]).last
if mval == '1': [qs_total.x(q) for q in cod]
qs_total.reset(qid=anc)
qs = qs_total.partial(qid=cod)
return qs
