Question

以下是MSF的典型优化配方：

using Microsoft.SolverFoundation.Services;

SolverContext context = SolverContext.GetContext();
Model model = context.CreateModel();

//decisions
Decision xs = new Decision(Domain.Real, "Number_of_small_chess_boards");
Decision xl = new Decision(Domain.Real, "Number_of_large_chess_boards");

model.AddDecisions(xs, xl);

//constraints
model.AddConstraints("limits", 0 <= xs, 0 <= xl);
model.AddConstraint("BoxWood", 1 * xs + 3 * xl <= 200);
model.AddConstraint("Lathe", 3 * xs + 2 * xl <= 160);

//Goals
model.AddGoal("Profit", GoalKind.Maximize, 5 * xs + 20 * xl);

// This doesn't work!
// model.AddGoal("Profit", GoalKind.Maximize, objfunc(xs, xl));


Solution sol = context.Solve(new SimplexDirective());
Report report = sol.GetReport();
Console.WriteLine(report);

是否可以使用单独的方法而不是像“5 * xs + 20 * xl”这样的语句作为目标函数？例如，如下所示的方法？怎么样？

// this method doesn't work!
static double objfunc(Decision x, Decision y)
{
    return 5 * x.ToDouble() + 20 * y.ToDouble();
}

Answer 1

就这么简单：

 static Term objfunc(Decision x, Decision y)
        {
            return 5 * x + 20 * y;
        }

该函数不必返回double，而是返回Term。

Answer 2

注意该函数不返回数字答案，而是一种评估答案的方法。如果你要重新编码为期限测试= 5 * x + 20 * y; String strTest = Test.ToString（）;

然后strTest会像（Add（mult（5，x），mult（20，y））;

方法作为Microsoft Solver Foundation中的目标函数？

2 个答案: