def test_default_fold(self):
bqm = dimod.BinaryQuadraticModel({'a': 1}, {}, 0, dimod.SPIN)
states = States(
State.from_sample(min_sample(bqm), bqm), # energy: -1
State.from_sample(max_sample(bqm), bqm), # energy: +1
)
best = ArgMin().run(states).result()
self.assertEqual(best.samples.first.energy, -1)
def test_basic(self):
bqm = dimod.BinaryQuadraticModel({}, {'ab': 1, 'bc': -1, 'ca': 1}, 0, dimod.SPIN)
state = State.from_sample(min_sample(bqm), bqm)
antistate = State.from_sample(max_sample(bqm), bqm)
result = GreedyPathMerge().run(States(state, antistate)).result()
self.assertEqual(result.samples.first.energy, -3.0)
def test_custom_fold(self):
bqm = dimod.BinaryQuadraticModel({'a': 1}, {}, 0, dimod.SPIN)
states = States(
State.from_sample(min_sample(bqm), bqm), # energy: -1
State.from_sample(max_sample(bqm), bqm), # energy: +1
)
fold = ArgMin(key=lambda s: -s.samples.first.energy)
best = fold.run(states).result()
self.assertEqual(best.samples.first.energy, 1)
def test_custom_key(self):
"""Custom key function works, here best state has the highest energy."""
bqm = dimod.BinaryQuadraticModel({'a': 1}, {}, 0, dimod.SPIN)
states = States(
State.from_sample(min_sample(bqm), bqm), # energy: -1
State.from_sample(max_sample(bqm), bqm), # energy: +1
)
tracker = TrackMin(key=lambda s: -s.samples.first.energy)
for state in states:
tracker.run(state).result()
self.assertEqual(tracker.best.samples.first.energy, +1)
def test_default_tracking(self):
"""Best seen state is kept (default: state with sampleset with the lowest energy)"""
bqm = dimod.BinaryQuadraticModel({'a': 1}, {}, 0, dimod.SPIN)
min_state = State.from_sample(min_sample(bqm), bqm) # energy: -1
max_state = State.from_sample(max_sample(bqm), bqm) # energy: +1
tracker = TrackMin()
_ = tracker.run(max_state).result()
self.assertEqual(tracker.best.samples.first.energy, +1)
_ = tracker.run(min_state).result()
self.assertEqual(tracker.best.samples.first.energy, -1)
_ = tracker.run(max_state).result()
self.assertEqual(tracker.best.samples.first.energy, -1)
