def test_n_hot_constraint():
c = NHotConstraint()
assert c.get_constraint_class() == "NHotConstraint"
assert c.get_variables() == set()
assert c.get_n() == 1
assert c.get_label() == "Default N-hot Constraint"
assert c.get_strength() == 1.0
x0 = pyqubo.Spin("x0")
x1 = pyqubo.Spin("x1")
x2 = pyqubo.Binary("x2")
c.add_variable(x0)
assert c.get_variables() == set([x0])
assert len(c.get_variables()) == 1
c.add_variable([x1, x2])
assert c.get_variables() == set([x0, x1, x2])
assert len(c.get_variables()) == 3
c.add_variable(set([x0]))
assert c.get_variables() == set([x0, x1, x2])
assert len(c.get_variables()) == 3
c.add_variable(variables=[x0, x1])
assert c.get_variables() == set([x0, x1, x2])
assert len(c.get_variables()) == 3
c.remove_variable(variables=[x0])
assert c.get_variables() == set([x1, x2])
assert len(c.get_variables()) == 2
with pytest.raises(ValueError):
c.remove_variable(variables=[x0])
def test_logical_model_to_physical_with_n_hot_constraint_randomly_qubo(qubo):
x = qubo.variables("x", shape=(4,))
c = NHotConstraint(x[(slice(0, 2),)], n=1, strength=10)
qubo.add_constraint(c)
c.add_variable(x[1])
c.add_variable(x[2])
c.add_variable(x)
physical = qubo.to_physical()
for i in range(3):
assert physical._raw_interactions[constants.INTERACTION_LINEAR][f"x[{i}]"] == 10.0
for i in range(2):
for j in range(i + 1, 3):
assert physical._raw_interactions[constants.INTERACTION_QUADRATIC][(f"x[{i}]", f"x[{j}]")] == -20.0
def test_logical_model_n_hot_constraint_y(ising):
y = ising.variables("y", shape=(2, 2))
ising.add_constraint(NHotConstraint(variables=y[0, :], n=2, label="my label"))
assert len(ising.get_constraints()) == 1
assert "my label" in ising.get_constraints()
assert ising.get_constraints_by_label("my label")._n == 2
# variables in list representation
c = NHotConstraint(variables=[y[1, 0], y[1, 1]], n=2, label="my label")
ising.add_constraint(c)
assert len(ising.get_constraints()) == 1
assert "my label" in ising.get_constraints()
assert len(ising.get_constraints_by_label("my label")._variables) == 2
assert ising.get_constraints_by_label("my label")._n == 2
# Constraint content changes
c.add_variable(variables=[y[0, 0]])
assert len(ising.get_constraints()) == 1
assert "my label" in ising.get_constraints()
assert len(ising.get_constraints_by_label("my label")._variables) == 3
assert ising.get_constraints_by_label("my label")._n == 2
def test_logical_model_to_physical_with_n_hot_constraint_randomly_ising(ising):
x = ising.variables("x", shape=(4,))
c = NHotConstraint(x[(slice(0, 2),)], n=1)
ising.add_constraint(c)
c.add_variable(x[1])
physical = ising.to_physical()
c.add_variable(x[2])
physical = ising.to_physical()
c.add_variable(x)
physical = ising.to_physical()
for i in range(3):
assert physical._raw_interactions[constants.INTERACTION_LINEAR][f"x[{i}]"] == -1.0
for i in range(2):
for j in range(i + 1, 3):
assert physical._raw_interactions[constants.INTERACTION_QUADRATIC][(f"x[{i}]", f"x[{j}]")] == -0.5