def test_label_conditions():
formula = Ite(a, Ite(b, v1, v2), v3)
variables = WMIVariables()
w = Weights(formula, variables)
labelled_formula, subs = w.label_conditions(formula)
assert len(subs) == 2
assert len(get_free_variables(labelled_formula)) == len(
get_free_variables(formula))
def test_find_conditions_with_subs():
formula = Ite(a, Ite(LT(x, v1), v2, v3), Ite(b, v1, v2))
variables = WMIVariables()
w = Weights(formula, variables)
subs = w._find_conditions(formula, {
a: Symbol("cond_0"),
y: Symbol("cond_1")
})
assert len(subs) == 4
def test_evaluate_weight():
formula = Ite(a, v1, v2)
variables = WMIVariables()
w = Weights(formula, variables)
value = w._evaluate_weight(w.weights, [True])
assert value == v1
value = w._evaluate_weight(w.weights, [False])
assert value == v2
def test_evaluate_weight_multiplication():
formula = Ite(a, v1, Times(v2, Ite(b, v1, v3)))
variables = WMIVariables()
w = Weights(formula, variables)
value = w._evaluate_weight(w.weights, [True, True])
assert value == v1
value = w._evaluate_weight(w.weights, [False, True])
assert value == Times(v2, v1)
value = w._evaluate_weight(w.weights, [False, False])
assert value == Times(v2, v3)
def test_weight_from_assignment():
formula = Ite(a, v1, Times(v2, Ite(LE(x, v1), v1, v3)))
variables = WMIVariables()
weight = Weights(formula, variables)
var = list(variables.variables.keys())
assignment = {var[0]: True, var[1]: True}
result, _ = weight.weight_from_assignment(assignment)
assert result == v1
assignment = {var[0]: False, var[1]: True}
result, _ = weight.weight_from_assignment(assignment)
assert result == Times(v2, v1)
assignment = {var[0]: False, var[1]: False}
result, _ = weight.weight_from_assignment(assignment)
assert result == Times(v2, v3)
def computeMI_batch(self, phis, **options):
"""Calculates the MI on a batch of queries.
Args:
phis (list(FNode)): The list of all the queries on which to calculate the MI.
**options:
- domA: set of pysmt vars encoding the Boolean integration domain (optional)
- domX: set of pysmt vars encoding the real integration domain (optional)
- mode: The mode to use when calculating MI.
Returns:
list(real): The list containing the result of each computation.
list(int): The list containing the number of integrations for each computation that have been computed.
"""
# save the old weight
old_weights = self.weights
old_variables = self.variables
# calculate wmi with constant weight
new_variables = WMIVariables()
new_weights = Weights(Real(1), new_variables)
self.weights = new_weights
self.variables = new_variables
volumes, integrations = self.computeWMI_batch(phis, **options)
# restore old weight
self.weights = old_weights
self.variables = old_variables
return volumes, integrations
def computeMI(self, phi, **options):
"""Calculates the MI on a single query.
Args:
phi (FNode): The query on which to calculate the MI.
**options:
- domA: set of pysmt vars encoding the Boolean integration domain (optional)
- domX: set of pysmt vars encoding the real integration domain (optional)
- mode: The mode to use when calculating MI.
Returns:
real: The result of the computation.
int: The number of integrations that have been computed.
"""
# save old weight
old_weights = self.weights
old_variables = self.variables
# calculate wmi with constant weight
new_variables = WMIVariables()
new_weights = Weights(Real(1), new_variables)
self.weights = new_weights
self.variables = new_variables
volume, n_integrations = self.computeWMI(phi, **options)
# restore old weight
self.weights = old_weights
self.variables = old_variables
return volume, n_integrations
def test_init():
formula = Ite(GE(x, v1), v1, Times(v2, Ite(b, v1, v3)))
variables = WMIVariables()
weight = Weights(formula, variables)
assert len(get_free_variables(weight.weights)) == len(
get_free_variables(formula))
assert len(weight.labels) == 2
assert len(get_free_variables(weight.labelling)) == 2 * 2
assert weight.n_conditions == 2
def __init__(self, chi, weight=Real(1), **options):
"""Default constructor.
Args:
chi (FNode): The support of the problem.
weight (FNode, optional): The weight of the problem (default: 1).
**options:
- n_threads: The number of threads to use when computing WMI.
"""
self.variables = WMIVariables()
self.weights = Weights(weight, self.variables)
self.chi = And(chi, self.weights.labelling)
n_threads = options.get("n_threads")
self.integrator = Latte_Integrator(n_threads = n_threads)
def test_find_conditions_count_no_conditions():
formula = Times(v1, Plus(v2, v3))
variables = WMIVariables()
w = Weights(formula, variables)
subs = w._find_conditions(formula, {})
assert len(subs) == 0
def test_find_conditions_count():
formula = Ite(a, Ite(LT(x, v1), v2, v3), Ite(b, v1, v2))
variables = WMIVariables()
w = Weights(formula, variables)
subs = w._find_conditions(formula, {})
assert len(subs) == 3
def test_init_not_correct_weight_function():
formula = GE(x, v1)
variables = WMIVariables()
with pytest.raises(WMIParsingException):
weight = Weights(formula, variables)