# MIPLearn: Extensible Framework for Learning-Enhanced Mixed-Integer Optimization # Copyright (C) 2020-2021, UChicago Argonne, LLC. All rights reserved. # Released under the modified BSD license. See COPYING.md for more details. from miplearn.features import ( FeaturesExtractor, InstanceFeatures, VariableFeatures, ConstraintFeatures, ) from miplearn.solvers.gurobi import GurobiSolver from miplearn.solvers.tests import ( assert_equals, _round, ) inf = float("inf") def test_knapsack() -> None: solver = GurobiSolver() instance = solver.build_test_instance_knapsack() model = instance.to_model() solver.set_instance(instance, model) solver.solve_lp() features = FeaturesExtractor().extract(instance, solver) assert features.variables is not None assert features.instance is not None assert_equals( _round(features.variables), VariableFeatures( names=["x[0]", "x[1]", "x[2]", "x[3]", "z"], basis_status=["U", "B", "U", "L", "U"], categories=["default", "default", "default", "default", None], lower_bounds=[0.0, 0.0, 0.0, 0.0, 0.0], obj_coeffs=[505.0, 352.0, 458.0, 220.0, 0.0], reduced_costs=[193.615385, 0.0, 187.230769, -23.692308, 13.538462], sa_lb_down=[-inf, -inf, -inf, -0.111111, -inf], sa_lb_up=[1.0, 0.923077, 1.0, 1.0, 67.0], sa_obj_down=[311.384615, 317.777778, 270.769231, -inf, -13.538462], sa_obj_up=[inf, 570.869565, inf, 243.692308, inf], sa_ub_down=[0.913043, 0.923077, 0.9, 0.0, 43.0], sa_ub_up=[2.043478, inf, 2.2, inf, 69.0], types=["B", "B", "B", "B", "C"], upper_bounds=[1.0, 1.0, 1.0, 1.0, 67.0], user_features=[ [23.0, 505.0], [26.0, 352.0], [20.0, 458.0], [18.0, 220.0], None, ], values=[1.0, 0.923077, 1.0, 0.0, 67.0], alvarez_2017=[ [1.0, 0.32899, 0.0, 0.0, 1.0, 1.0, 5.265874, 46.051702], [1.0, 0.229316, 0.0, 0.076923, 1.0, 1.0, 3.532875, 5.388476], [1.0, 0.298371, 0.0, 0.0, 1.0, 1.0, 5.232342, 46.051702], [1.0, 0.143322, 0.0, 0.0, 1.0, -1.0, 46.051702, 3.16515], [0.0, 0.0, 0.0, 0.0, 1.0, -1.0, 0.0, 0.0], ], ), ) assert_equals( _round(features.constraints), ConstraintFeatures( basis_status=("N",), categories=("eq_capacity",), dual_values=(13.538462,), names=("eq_capacity",), lazy=(False,), lhs=( ( ("x[0]", 23.0), ("x[1]", 26.0), ("x[2]", 20.0), ("x[3]", 18.0), ("z", -1.0), ), ), rhs=(0.0,), sa_rhs_down=(-24.0,), sa_rhs_up=(2.0,), senses=("=",), slacks=(0.0,), user_features=((0.0,),), ), ) assert_equals( features.instance, InstanceFeatures( user_features=[67.0, 21.75], lazy_constraint_count=0, ), ) def test_constraint_getindex() -> None: cf = ConstraintFeatures( names=("c1", "c2", "c3"), rhs=(1.0, 2.0, 3.0), senses=("=", "<", ">"), lhs=( ( ("x1", 1.0), ("x2", 1.0), ), ( ("x2", 2.0), ("x3", 2.0), ), ( ("x3", 3.0), ("x4", 3.0), ), ), ) assert_equals( cf[True, False, True], ConstraintFeatures( names=("c1", "c3"), rhs=(1.0, 3.0), senses=("=", ">"), lhs=( ( ("x1", 1.0), ("x2", 1.0), ), ( ("x3", 3.0), ("x4", 3.0), ), ), ), )