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35 lines
947 B
35 lines
947 B
# MIPLearn: Extensible Framework for Learning-Enhanced Mixed-Integer Optimization
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# Copyright (C) 2020, UChicago Argonne, LLC. All rights reserved.
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# Released under the modified BSD license. See COPYING.md for more details.
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import MIPLearn: to_model,
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get_instance_features,
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get_variable_features
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find_violated_lazy_constraints
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using JuMP
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struct KnapsackData
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weights
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prices
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capacity
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end
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function to_model(data::KnapsackData)
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model = Model()
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n = length(data.weights)
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@variable(model, x[1:n], Bin)
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@objective(model, Max, sum(x[i] * data.prices[i] for i in 1:n))
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@constraint(model, sum(x[i] * data.weights[i] for i in 1:n) <= data.capacity)
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return model
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end
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function get_instance_features(data::KnapsackData)
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return [0.]
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end
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function get_variable_features(data::KnapsackData, var, index)
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return [0.]
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end
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KnapsackInstance = @Instance(KnapsackData)
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