def test_sample_memory_ghz(self):
"""Test sample_memory method for GHZ state"""
shots = 2000
state = DensityMatrix(
(Statevector.from_label("000") + Statevector.from_label("111")) / np.sqrt(2)
)
state.seed(100)
# 3-qubit qargs
target = {"000": shots / 2, "111": shots / 2}
for qargs in [[0, 1, 2], [2, 1, 0], [1, 2, 0], [1, 0, 2]]:
with self.subTest(msg=f"memory (qargs={qargs})"):
memory = state.sample_memory(shots, qargs=qargs)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), set(target))
# 2-qubit qargs
target = {"00": shots / 2, "11": shots / 2}
for qargs in [[0, 1], [2, 1], [1, 2], [1, 2]]:
with self.subTest(msg=f"memory (qargs={qargs})"):
memory = state.sample_memory(shots, qargs=qargs)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), set(target))
# 1-qubit qargs
target = {"0": shots / 2, "1": shots / 2}
for qargs in [[0], [1], [2]]:
with self.subTest(msg=f"memory (qargs={qargs})"):
memory = state.sample_memory(shots, qargs=qargs)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), set(target))
def test_sample_memory_w(self):
"""Test sample_memory method for W state"""
shots = 3000
state = DensityMatrix(
(Statevector.from_label('001') + Statevector.from_label('010') +
Statevector.from_label('100')) / np.sqrt(3))
state.seed(100)
target = {'001': shots / 3, '010': shots / 3, '100': shots / 3}
for qargs in [[0, 1, 2], [2, 1, 0], [1, 2, 0], [1, 0, 2]]:
with self.subTest(msg='memory (qargs={})'.format(qargs)):
memory = state.sample_memory(shots, qargs=qargs)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), set(target))
# 2-qubit qargs
target = {'00': shots / 3, '01': shots / 3, '10': shots / 3}
for qargs in [[0, 1], [2, 1], [1, 2], [1, 2]]:
with self.subTest(msg='memory (qargs={})'.format(qargs)):
memory = state.sample_memory(shots, qargs=qargs)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), set(target))
# 1-qubit qargs
target = {'0': 2 * shots / 3, '1': shots / 3}
for qargs in [[0], [1], [2]]:
with self.subTest(msg='memory (qargs={})'.format(qargs)):
memory = state.sample_memory(shots, qargs=qargs)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), set(target))
def test_sample_memory_qutrit(self):
"""Test sample_memory method for qutrit state"""
p = 0.3
shots = 1000
state = DensityMatrix(np.diag([p, 0, 1 - p]))
state.seed(100)
with self.subTest(msg="memory"):
memory = state.sample_memory(shots)
self.assertEqual(len(memory), shots)
self.assertEqual(set(memory), {"0", "2"})