def find_isomorphism(G1, G2):
"""Search for isomorphism between two graphs
Args:
G1 (networkx.Graph)
G2 (networkx.Graph)
Returns:
If no isomorphism is found, returns None. Otherwise, returns
dict with keys as nodes from graph 1 and values as
corresponding nodes from graph 2.
"""
if G1.number_of_nodes() != G2.number_of_nodes():
return None
dqm = create_dqm(G1, G2)
sampler = LeapHybridDQMSampler()
results = sampler.sample_dqm(dqm, label='Example - Circuit Equivalence')
best = results.first
# Note: with this formulation, the ground state energy for an
# isomorphism is -A*N, where A is the penalty coefficient
# associated with the H_A term, currently assumed to be 1.
if np.isclose(best.energy, -G1.number_of_nodes()):
G2_nodes = list(G2.nodes)
return {k: G2_nodes[i] for k, i in best.sample.items()}
else:
# Isomorphism not found
return None
def find_isomorphism(G1, G2):
"""Search for isomorphism between two graphs
Args:
G1 (networkx.Graph)
G2 (networkx.Graph)
Returns:
If no isomorphism is found, returns None. Otherwise, returns
dict with keys as nodes from graph 1 and values as
corresponding nodes from graph 2.
"""
if G1.number_of_nodes() != G2.number_of_nodes():
return None
dqm = create_dqm(G1, G2)
sampler = LeapHybridDQMSampler()
results = sampler.sample_dqm(dqm, label='Example - Circuit Equivalence')
best = results.first
if np.isclose(best.energy, 0.0):
G2_nodes = list(G2.nodes)
return {k: G2_nodes[i] for k, i in best.sample.items()}
else:
# Isomorphism not found
return None
def solve(adj_nodes, adj_edges, even_dist=False):
dqm = DiscreteQuadraticModel()
for i in adj_nodes:
dqm.add_variable(NURSES, label=i)
# classic graph coloring constraint that no two adjacent nodes have the same color
for i0, i1 in adj_edges:
dqm.set_quadratic(i0, i1, {(c, c): LAGRANGE for c in range(NURSES)})
shifts_per_nurse = DAYS * SHIFTS // NURSES
if even_dist:
# we should ensure that nurses get assigned a roughly equal amount of work
for i in range(NURSES):
for index, j in enumerate(adj_nodes):
dqm.set_linear_case(
j, i,
dqm.get_linear_case(j, i) - LAGRANGE *
(2 * shifts_per_nurse + 1))
for k_index in range(index + 1, len(adj_nodes)):
k = adj_nodes[k_index]
dqm.set_quadratic_case(
j, i, k, i,
LAGRANGE * (dqm.get_quadratic_case(j, i, k, i) + 2))
# some nurses may hate each other, so we should do out best to not put them in the same shift!
for d in range(DAYS):
for s in range(SHIFTS):
for l1 in range(NURSES_PER_SHIFT):
for l2 in range(l1 + 1, NURSES_PER_SHIFT):
j = f"l{l1}_d{d}_s{s}"
k = f"l{l2}_d{d}_s{s}"
for conflict in CONFLICTS:
for n1 in conflict:
for n2 in conflict:
if n1 == n2:
continue
dqm.set_quadratic_case(
j, n1, k, n2,
LAGRANGE2 *
(dqm.get_quadratic_case(j, n1, k, n2) +
10))
sampler = LeapHybridDQMSampler(token=API_TOKEN)
sampleset = sampler.sample_dqm(dqm, time_limit=10)
sample = sampleset.first.sample
energy = sampleset.first.energy
return sample, energy
def run_hybrid_solver(dqm):
"""Solve DQM using hybrid solver through the cloud."""
print("\nRunning hybrid sampler...")
# Initialize the DQM solver
sampler = LeapHybridDQMSampler()
# Solve the problem using the DQM solver
sampleset = sampler.sample_dqm(dqm, label='Example - Map Coloring')
return sampleset
def find_equivalence(C1, C2):
"""Search for equivalence between two circuits
This requires that the corresponding graphs are isomorphic and
that matched nodes are "equivalent". In particular, transistor
types must match.
Args:
C1 (Circuit)
C2 (Circuit)
Returns:
If no equivalence is found, returns None. Otherwise, returns
dict with keys as nodes from graph 1 and values as
corresponding nodes from graph 2.
"""
if C1.G.number_of_nodes() != C2.G.number_of_nodes():
return None
dqm = create_dqm(C1.G, C2.G)
sampler = LeapHybridDQMSampler()
results = sampler.sample_dqm(dqm, label='Example - Circuit Equivalence')
if not np.isclose(results.first.energy, -C1.G.number_of_nodes()):
return None
G2_nodes = list(C2.G.nodes)
for sample, energy in results.data(fields=['sample', 'energy']):
if np.isclose(energy, -C1.G.number_of_nodes()):
# Now check that the transistor types match
mapping = {k: G2_nodes[i] for k, i in sample.items()}
valid = True
for n1, n2 in mapping.items():
if ('nMOS' in n1
and 'nMOS' not in n2) or ('pMOS' in n1
and 'pMOS' not in n2):
valid = False
break
if valid:
return mapping
else:
# Sample is not an isomorphism
return None
return None
def solveSudoku(dqm, G):
'''
This method solves the sudoku and also verify the result
Parameters:
dqm : Discrete Quadratic Model object
G : networkx graph object, which represents the modelled graph
Returns:
valid : Boolean variable which tells if the solution is valid or invalid
solution : 2D solution list to our Sudoku problem
'''
sampler = LeapHybridDQMSampler()
sampleset = sampler.sample_dqm(dqm)
sample = sampleset.first.sample
energy = sampleset.first.energy
valid = True
for edge in G.edges:
i, j = edge
if (sample[i] == sample[j]):
valid = False
break
print("Solution :", sample)
print("Solution Energy :", energy)
print("Solution validty:", valid)
global_row = int(math.sqrt(len(G.nodes())))
solution = []
for i in range(1, (global_row**2) + 1):
row = []
row.append(sample[i])
print(sample[i] + 1, end=' ')
if ((i) % global_row == 0):
print("\n")
solution.append(row)
return valid, solution
def test_DQM_subclass_without_serialization_can_be_sampled(self):
"""Test that DQM subclasses that do not implement serialization can
still be sampled by LeapHybridDQMSampler.
Sampling requires serialization. LeapHybridDQMSampler calls
DQM.to_file(dqm, ...) if dqm.to_file(...) raises NotImplementedError.
"""
class DQMWithoutSerialization(dimod.DQM):
def to_file(self, *args, **kwargs):
raise NotImplementedError
class MockSampleset:
def relabel_variables(self, *args):
return self
class MockFuture:
sampleset = MockSampleset()
class MockSolver:
properties = dict(category='hybrid',
minimum_time_limit=[[10000, 1.0]])
supported_problem_types = ['dqm']
def sample_dqm(self, *args, **kwargs):
return MockFuture()
class MockClient:
@classmethod
def from_config(cls, *args, **kwargs):
return cls()
def get_solver(self, *args, **kwargs):
return MockSolver()
with patch('dwave.system.samplers.leap_hybrid_sampler.Client',
MockClient):
sampler = LeapHybridDQMSampler()
dqm = DQMWithoutSerialization()
sampler.sample_dqm(dqm)
def test_time_limit_exceptions(self):
class MockSolver():
properties = dict(
category='hybrid',
minimum_time_limit=[[20000, 5.0], [100000, 6.0],
[200000, 13.0], [500000, 34.0],
[1000000, 71.0], [2000000, 152.0],
[5000000, 250.0], [20000000, 400.0],
[250000000, 1200.0]],
maximum_time_limit_hrs=24.0,
)
supported_problem_types = ['dqm']
def sample_dqm(self, *args, **kwargs):
raise RuntimeError
class MockClient():
@classmethod
def from_config(cls, *args, **kwargs):
return cls()
def get_solver(self, *args, **kwargs):
return MockSolver()
with patch('dwave.system.samplers.leap_hybrid_sampler.Client',
MockClient):
sampler = LeapHybridDQMSampler()
dqm = dimod.DQM()
with self.assertRaises(ValueError):
sampler.sample_dqm(dqm, time_limit=1)
with self.assertRaises(ValueError):
sampler.sample_dqm(dqm, time_limit=10000000)
def test_illegal_edges(self):
"""Run demo.py and check that no illegal edges are reported. This ensures the lagrange parameter is set appropriately."""
t0 = time.perf_counter()
args = demo.read_in_args(["--graph", "internet"])
G = demo.build_graph(args)
dqm = demo.build_dqm(G)
sampler = LeapHybridDQMSampler()
sample = demo.run_dqm_and_collect_solutions(dqm, sampler)
group_1, group_2, sep_group, illegal_edges = demo.process_sample(G, sample)
self.assertEqual(len(illegal_edges), 0)
run_time = time.perf_counter() - t0
print("illegal edges time: ", run_time)
if __name__ == '__main__':
passenger_demand, leg_cost, num_cities = read_inputs(flow_file='flow.csv',
cost_file='cost.csv')
city_names, city_lats, city_longs = read_city_info('city-data.txt')
p = 3 # number of hubs
a = 0.4 # discount for hub-hub routes
# Uncomment lines below to visualize total network options
# G = build_graph(passenger_demand, city_names)
# draw_graph(G, city_names, city_lats, city_longs)
dqm = build_dqm(passenger_demand, leg_cost, num_cities, p, a)
print("\nRunning hybrid solver...\n")
sampler = LeapHybridDQMSampler()
sampleset = sampler.sample_dqm(dqm, label='Example - DQM Airline Hubs')
print("\nInterpreting solutions...\n")
ss = list(sampleset.data(['sample']))
cost_dict = {
index: get_cost(ss[index].sample, a, passenger_demand, leg_cost,
num_cities)
for index in range(len(ss))
}
ordered_samples = dict(
sorted(cost_dict.items(), key=lambda item: item[1], reverse=True))
filenames = []
def set_sampler():
'''Returns a dimod sampler'''
sampler = LeapHybridDQMSampler()
return sampler
lagrange = 10
num_colors = 4
colors = range(num_colors)
dqm = DiscreteQuadraticModel()
G = nx.Graph()
G.add_edges_from([(0, 1), (1, 2), (2, 3), (3, 4), (4, 5), (5, 6), (0, 6)])
n_edges = len(G.edges)
for p in G.nodes:
dqm.add_variable(num_colors, label=p)
for p in G.nodes:
dqm.set_linear(p, colors)
for p0, p1 in G.edges:
dqm.set_quadratic(p0, p1, {(c, c): lagrange for c in colors})
for p0, p1 in G.edges:
dqm.set_quadratic(p0, p1, {(c, c): lagrange for c in colors})
sampler = LeapHybridDQMSampler()
sampleset = sampler.sample_dqm(dqm)
sample = sampleset.first.sample
energy = sampleset.first.energy
valid = True
for edge in G.edges:
i, j = edge
if sample[i] == sample[j]:
valid = False
break
print("Solution: ", sample)
print("Solution energy: ", energy)
print("Solution validity: ", valid)
for p in G.nodes:
linear_term = constraint_const + (0.5 * np.ones(num_partitions) *
G.degree[p])
dqm.set_linear(p, linear_term)
# Quadratic term for node pairs which do not have edges between them
for p0, p1 in nx.non_edges(G):
dqm.set_quadratic(p0, p1, {(c, c): (2 * lagrange) for c in partitions})
# Quadratic term for node pairs which have edges between them
for p0, p1 in G.edges:
dqm.set_quadratic(p0, p1, {(c, c): ((2 * lagrange) - 1)
for c in partitions})
# Initialize the DQM solver
sampler = LeapHybridDQMSampler()
# Solve the problem using the DQM solver
offset = lagrange * num_nodes * num_nodes / num_partitions
sampleset = sampler.sample_dqm(dqm, label='Example - Graph Partitioning DQM')
# get the first solution
sample = sampleset.first.sample
energy = sampleset.first.energy
# Count the nodes in each partition
counts = np.zeros(num_partitions)
for i in sample:
counts[sample[i]] += 1
# Compute the number of links between different partitions
qb_cols = []
qb_biases = []
for i in range(rows * cols):
for j in range(i + 1, rows * cols):
for case in range(num_segments):
qb_rows.append(i * num_segments + case)
qb_cols.append(j * num_segments + case)
qb_biases.append(weight(i, j, img))
quadratic_biases = (np.asarray(qb_rows), np.asarray(qb_cols),
np.asarray(qb_biases))
dqm = DiscreteQuadraticModel.from_numpy_vectors(case_starts, linear_biases,
quadratic_biases)
# Initialize the DQM solver
print("\nRunning DQM solver...")
sampler = LeapHybridDQMSampler()
# Solve the problem using the DQM solver
sampleset = sampler.sample_dqm(dqm, label='Example - Image Segmentation')
# Get the first solution
sample = sampleset.first.sample
print("\nProcessing solution...")
im_segmented = np.zeros((rows, cols))
for key, val in sample.items():
x, y = unindexing(key)
im_segmented[x, y] = val
if random:
row_indices = [1 + i for i in range(rows - 1)]
first_letters = set()
coefficient_map = defaultdict(int)
lhs_list, rhs_list, problem_statement = parse_problem_file(args.filename)
update_coefficient_map_and_first_letter_set(lhs_list, 1, coefficient_map,
first_letters)
update_coefficient_map_and_first_letter_set(rhs_list, -1, coefficient_map,
first_letters)
variable_list = []
for variable, coefficient in coefficient_map.items():
variable_list.append(
LetterVariable(variable,
coefficient,
first_letter=variable in first_letters))
pprint(variable_list)
dqm = build_dqm(variable_list, coefficient_map)
# Send DQM to LeapHybridDQMSampler, get response
response = LeapHybridDQMSampler().sample_dqm(
dqm, time_limit=5, label="Example - Cryptarithmetic").aggregate()
lowest_energy_sample = response.first.sample
render_solution(lowest_energy_sample, variable_list, lhs_list, rhs_list,
problem_statement)
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
import os
import unittest
import dimod
import numpy as np
from dwave.cloud.exceptions import ConfigFileError, SolverNotFoundError
from dwave.system import LeapHybridDQMSampler
try:
sampler = LeapHybridDQMSampler()
except (ValueError, ConfigFileError, SolverNotFoundError):
sampler = None
@unittest.skipIf(os.getenv('SKIP_INT_TESTS'), "Skipping integration test.")
@unittest.skipIf(sampler is None, "no hybrid sampler available")
class TestLeapHybridSampler(unittest.TestCase):
def test_smoke(self):
dqm = dimod.DQM()
u = dqm.add_variable(2, 'a')
v = dqm.add_variable(3)
dqm.set_linear(u, [1, 2])
dqm.set_quadratic(u, v, {(0, 1): 1, (0, 2): 1})
try:
lagrange = max(colors)
# Load the DQM. Define the variables, and then set biases and weights.
# We set the linear biases to favor lower-numbered colors; this will
# have the effect of minimizing the number of colors used.
# We penalize edge connections by the Lagrange parameter, to encourage
# connected nodes to have different colors.
for p in G.nodes:
dqm.add_variable(num_colors, label=p)
for p in G.nodes:
dqm.set_linear(p, colors)
for p0, p1 in G.edges:
dqm.set_quadratic(p0, p1, {(c, c): lagrange for c in colors})
# Initialize the DQM solver
sampler = LeapHybridDQMSampler()
# Solve the problem using the DQM solver
sampleset = sampler.sample_dqm(dqm, label='Example - Graph Coloring')
# get the first solution, and print it
sample = sampleset.first.sample
energy = sampleset.first.energy
# check that colors are different
valid = True
for edge in G.edges:
i, j = edge
if sample[i] == sample[j]:
valid = False
break
# Build the DQM starting by adding variables
for name in range(num_employees):
dqm.add_variable(num_shifts, label=name)
# Distribute employees equally across shifts according to preferences
num_per_shift = int(num_employees/num_shifts)
gamma = 1/(num_employees*num_shifts)
for i in range(num_shifts):
for j in range(num_employees):
dqm.set_linear_case(j, i, dqm.get_linear_case(j, i) - gamma*(2*num_per_shift+1))
for k in range(j+1, num_employees):
dqm.set_quadratic_case(j, i, k, i, gamma*(dqm.get_quadratic_case(j, i, k, i) + 2))
# Initialize the DQM solver
sampler = LeapHybridDQMSampler()
# Solve the problem using the DQM solver
sampleset = sampler.sample_dqm(dqm, label='Example - Employee Scheduling')
# Get the first solution, and print it
# Mi da la soluzione migliore, quella in cui sono caduto più volte e me la salvo
sample = sampleset.first.sample
energy = sampleset.first.energy
print("\nSchedule score:", energy)
# Build schedule
schedule = np.ones((num_employees, num_shifts))*num_shifts
prefs = [0]*num_shifts
shifts = [0]*num_shifts
for key, val in sample.items():