DropRedundant: Collect data from multiple runs

This commit is contained in:
2021-01-14 11:27:47 -06:00
parent e12a896504
commit 7e4b1d77a3
3 changed files with 157 additions and 56 deletions

View File

@@ -50,11 +50,9 @@ class DropRedundantInequalitiesStep(Component):
self.current_iteration = 0
logger.info("Predicting redundant LP constraints...")
cids = solver.internal_solver.get_constraint_ids()
x, constraints = self.x(
[instance],
constraint_ids=cids,
return_constraints=True,
x, constraints = self._x_test(
instance,
constraint_ids=solver.internal_solver.get_constraint_ids(),
)
y = self.predict(x)
@@ -84,11 +82,16 @@ class DropRedundantInequalitiesStep(Component):
stats,
training_data,
):
instance.slacks = solver.internal_solver.get_inequality_slacks()
stats["DropRedundant: Kept"] = self.total_kept
stats["DropRedundant: Dropped"] = self.total_dropped
stats["DropRedundant: Restored"] = self.total_restored
stats["DropRedundant: Iterations"] = self.total_iterations
if "slacks" not in training_data.keys():
training_data["slacks"] = solver.internal_solver.get_inequality_slacks()
stats.update(
{
"DropRedundant: Kept": self.total_kept,
"DropRedundant: Dropped": self.total_dropped,
"DropRedundant: Restored": self.total_restored,
"DropRedundant: Iterations": self.total_iterations,
}
)
def fit(self, training_instances):
logger.debug("Extracting x and y...")
@@ -100,33 +103,45 @@ class DropRedundantInequalitiesStep(Component):
self.classifiers[category] = deepcopy(self.classifier_prototype)
self.classifiers[category].fit(x[category], y[category])
def x(self, instances, constraint_ids=None, return_constraints=False):
def _x_test(self, instance, constraint_ids):
x = {}
constraints = {}
cids = constraint_ids
for cid in cids:
category = instance.get_constraint_category(cid)
if category is None:
continue
if category not in x:
x[category] = []
constraints[category] = []
x[category] += [instance.get_constraint_features(cid)]
constraints[category] += [cid]
for category in x.keys():
x[category] = np.array(x[category])
return x, constraints
def _x_train(self, instances):
x = {}
for instance in tqdm(
InstanceIterator(instances),
desc="Extract (rlx:drop_ineq:x)",
disable=len(instances) < 5,
):
if constraint_ids is not None:
cids = constraint_ids
else:
cids = instance.slacks.keys()
for cid in cids:
category = instance.get_constraint_category(cid)
if category is None:
continue
if category not in x:
x[category] = []
constraints[category] = []
x[category] += [instance.get_constraint_features(cid)]
constraints[category] += [cid]
for training_data in instance.training_data:
cids = training_data["slacks"].keys()
for cid in cids:
category = instance.get_constraint_category(cid)
if category is None:
continue
if category not in x:
x[category] = []
x[category] += [instance.get_constraint_features(cid)]
for category in x.keys():
x[category] = np.array(x[category])
if return_constraints:
return x, constraints
else:
return x
return x
def x(self, instances):
return self._x_train(instances)
def y(self, instances):
y = {}
@@ -135,16 +150,17 @@ class DropRedundantInequalitiesStep(Component):
desc="Extract (rlx:drop_ineq:y)",
disable=len(instances) < 5,
):
for (cid, slack) in instance.slacks.items():
category = instance.get_constraint_category(cid)
if category is None:
continue
if category not in y:
y[category] = []
if slack > self.slack_tolerance:
y[category] += [[1]]
else:
y[category] += [[0]]
for training_data in instance.training_data:
for (cid, slack) in training_data["slacks"].items():
category = instance.get_constraint_category(cid)
if category is None:
continue
if category not in y:
y[category] = []
if slack > self.slack_tolerance:
y[category] += [[1]]
else:
y[category] += [[0]]
return y
def predict(self, x):

View File

@@ -0,0 +1,370 @@
# MIPLearn: Extensible Framework for Learning-Enhanced Mixed-Integer Optimization
# Copyright (C) 2020, UChicago Argonne, LLC. All rights reserved.
# Released under the modified BSD license. See COPYING.md for more details.
import numpy as np
from unittest.mock import Mock, call
from miplearn import (
LearningSolver,
Instance,
InternalSolver,
GurobiSolver,
)
from miplearn.classifiers import Classifier
from miplearn.components.relaxation import (
DropRedundantInequalitiesStep,
RelaxIntegralityStep,
)
from miplearn.problems.knapsack import GurobiKnapsackInstance
def _setup():
solver = Mock(spec=LearningSolver)
internal = solver.internal_solver = Mock(spec=InternalSolver)
internal.get_constraint_ids = Mock(return_value=["c1", "c2", "c3", "c4"])
internal.get_inequality_slacks = Mock(
side_effect=lambda: {
"c1": 0.5,
"c2": 0.0,
"c3": 0.0,
"c4": 1.4,
}
)
internal.extract_constraint = Mock(side_effect=lambda cid: "<%s>" % cid)
internal.is_constraint_satisfied = Mock(return_value=False)
instance = Mock(spec=Instance)
instance.get_constraint_features = Mock(
side_effect=lambda cid: {
"c2": np.array([1.0, 0.0]),
"c3": np.array([0.5, 0.5]),
"c4": np.array([1.0]),
}[cid]
)
instance.get_constraint_category = Mock(
side_effect=lambda cid: {
"c1": None,
"c2": "type-a",
"c3": "type-a",
"c4": "type-b",
}[cid]
)
classifiers = {
"type-a": Mock(spec=Classifier),
"type-b": Mock(spec=Classifier),
}
classifiers["type-a"].predict_proba = Mock(
return_value=np.array(
[
[0.20, 0.80],
[0.05, 0.95],
]
)
)
classifiers["type-b"].predict_proba = Mock(
return_value=np.array(
[
[0.02, 0.98],
]
)
)
return solver, internal, instance, classifiers
def test_drop_redundant():
solver, internal, instance, classifiers = _setup()
component = DropRedundantInequalitiesStep()
component.classifiers = classifiers
# LearningSolver calls before_solve
component.before_solve(solver, instance, None)
# Should query list of constraints
internal.get_constraint_ids.assert_called_once()
# Should query category and features for each constraint in the model
assert instance.get_constraint_category.call_count == 4
instance.get_constraint_category.assert_has_calls(
[
call("c1"),
call("c2"),
call("c3"),
call("c4"),
]
)
# For constraint with non-null categories, should ask for features
assert instance.get_constraint_features.call_count == 3
instance.get_constraint_features.assert_has_calls(
[
call("c2"),
call("c3"),
call("c4"),
]
)
# Should ask ML to predict whether constraint should be removed
type_a_actual = component.classifiers["type-a"].predict_proba.call_args[0][0]
type_b_actual = component.classifiers["type-b"].predict_proba.call_args[0][0]
np.testing.assert_array_equal(type_a_actual, np.array([[1.0, 0.0], [0.5, 0.5]]))
np.testing.assert_array_equal(type_b_actual, np.array([[1.0]]))
# Should ask internal solver to remove constraints predicted as redundant
assert internal.extract_constraint.call_count == 2
internal.extract_constraint.assert_has_calls(
[
call("c3"),
call("c4"),
]
)
# LearningSolver calls after_solve
training_data = {}
component.after_solve(solver, instance, None, {}, training_data)
# Should query slack for all inequalities
internal.get_inequality_slacks.assert_called_once()
# Should store constraint slacks in instance object
assert training_data["slacks"] == {
"c1": 0.5,
"c2": 0.0,
"c3": 0.0,
"c4": 1.4,
}
def test_drop_redundant_with_check_feasibility():
solver, internal, instance, classifiers = _setup()
component = DropRedundantInequalitiesStep(
check_feasibility=True,
violation_tolerance=1e-3,
)
component.classifiers = classifiers
# LearningSolver call before_solve
component.before_solve(solver, instance, None)
# Assert constraints are extracted
assert internal.extract_constraint.call_count == 2
internal.extract_constraint.assert_has_calls(
[
call("c3"),
call("c4"),
]
)
# LearningSolver calls iteration_cb (first time)
should_repeat = component.iteration_cb(solver, instance, None)
# Should ask LearningSolver to repeat
assert should_repeat
# Should ask solver if removed constraints are satisfied (mock always returns false)
internal.is_constraint_satisfied.assert_has_calls(
[
call("<c3>", 1e-3),
call("<c4>", 1e-3),
]
)
# Should add constraints back to LP relaxation
internal.add_constraint.assert_has_calls([call("<c3>"), call("<c4>")])
# LearningSolver calls iteration_cb (second time)
should_repeat = component.iteration_cb(solver, instance, None)
assert not should_repeat
def test_x_y_fit_predict_evaluate():
instances = [Mock(spec=Instance), Mock(spec=Instance)]
component = DropRedundantInequalitiesStep(slack_tolerance=0.05, threshold=0.80)
component.classifiers = {
"type-a": Mock(spec=Classifier),
"type-b": Mock(spec=Classifier),
}
component.classifiers["type-a"].predict_proba = Mock(
return_value=[
np.array([0.20, 0.80]),
]
)
component.classifiers["type-b"].predict_proba = Mock(
return_value=np.array(
[
[0.50, 0.50],
[0.05, 0.95],
]
)
)
# First mock instance
instances[0].training_data = [
{
"slacks": {
"c1": 0.00,
"c2": 0.05,
"c3": 0.00,
"c4": 30.0,
}
}
]
instances[0].get_constraint_category = Mock(
side_effect=lambda cid: {
"c1": None,
"c2": "type-a",
"c3": "type-a",
"c4": "type-b",
}[cid]
)
instances[0].get_constraint_features = Mock(
side_effect=lambda cid: {
"c2": np.array([1.0, 0.0]),
"c3": np.array([0.5, 0.5]),
"c4": np.array([1.0]),
}[cid]
)
# Second mock instance
instances[1].training_data = [
{
"slacks": {
"c1": 0.00,
"c3": 0.30,
"c4": 0.00,
"c5": 0.00,
}
}
]
instances[1].get_constraint_category = Mock(
side_effect=lambda cid: {
"c1": None,
"c3": "type-a",
"c4": "type-b",
"c5": "type-b",
}[cid]
)
instances[1].get_constraint_features = Mock(
side_effect=lambda cid: {
"c3": np.array([0.3, 0.4]),
"c4": np.array([0.7]),
"c5": np.array([0.8]),
}[cid]
)
expected_x = {
"type-a": np.array(
[
[1.0, 0.0],
[0.5, 0.5],
[0.3, 0.4],
]
),
"type-b": np.array(
[
[1.0],
[0.7],
[0.8],
]
),
}
expected_y = {
"type-a": np.array([[0], [0], [1]]),
"type-b": np.array([[1], [0], [0]]),
}
# Should build X and Y matrices correctly
actual_x = component.x(instances)
actual_y = component.y(instances)
for category in ["type-a", "type-b"]:
np.testing.assert_array_equal(actual_x[category], expected_x[category])
np.testing.assert_array_equal(actual_y[category], expected_y[category])
# Should pass along X and Y matrices to classifiers
component.fit(instances)
for category in ["type-a", "type-b"]:
actual_x = component.classifiers[category].fit.call_args[0][0]
actual_y = component.classifiers[category].fit.call_args[0][1]
np.testing.assert_array_equal(actual_x, expected_x[category])
np.testing.assert_array_equal(actual_y, expected_y[category])
assert component.predict(expected_x) == {"type-a": [[1]], "type-b": [[0], [1]]}
ev = component.evaluate(instances[1])
assert ev["True positive"] == 1
assert ev["True negative"] == 1
assert ev["False positive"] == 1
assert ev["False negative"] == 0
def test_x_multiple_solves():
instance = Mock(spec=Instance)
instance.training_data = [
{
"slacks": {
"c1": 0.00,
"c2": 0.05,
"c3": 0.00,
"c4": 30.0,
}
},
{
"slacks": {
"c1": 0.00,
"c2": 0.00,
"c3": 1.00,
"c4": 0.0,
}
},
]
instance.get_constraint_category = Mock(
side_effect=lambda cid: {
"c1": None,
"c2": "type-a",
"c3": "type-a",
"c4": "type-b",
}[cid]
)
instance.get_constraint_features = Mock(
side_effect=lambda cid: {
"c2": np.array([1.0, 0.0]),
"c3": np.array([0.5, 0.5]),
"c4": np.array([1.0]),
}[cid]
)
expected_x = {
"type-a": np.array(
[
[1.0, 0.0],
[0.5, 0.5],
[1.0, 0.0],
[0.5, 0.5],
]
),
"type-b": np.array(
[
[1.0],
[1.0],
]
),
}
expected_y = {
"type-a": np.array([[1], [0], [0], [1]]),
"type-b": np.array([[1], [0]]),
}
# Should build X and Y matrices correctly
component = DropRedundantInequalitiesStep()
actual_x = component.x([instance])
actual_y = component.y([instance])
print(actual_x)
for category in ["type-a", "type-b"]:
np.testing.assert_array_equal(actual_x[category], expected_x[category])
np.testing.assert_array_equal(actual_y[category], expected_y[category])