用约束求解多变量方程 - Choco

Question

我想用这样的离散值求解非线性多变量方程：

x*y + z + t - 10 = 0

有约束：

10 < x < 100

等等..

我正在尝试使用Choco库，但我有点失落。我找到了这段代码：

    // 1. Create a Solver
    Solver solver = new Solver("my first problem");
    // 2. Create variables through the variable factory
    IntVar x = VariableFactory.bounded("X", 0, 5, solver);
    IntVar y = VariableFactory.bounded("Y", 0, 5, solver);
    // 3. Create and post constraints by using constraint factories
    solver.post(IntConstraintFactory.arithm(x, "+", y, "<", 5));
    // 4. Define the search strategy
    solver.set(IntStrategyFactory.lexico_LB(x, y));
    // 5. Launch the resolution process
    solver.findSolution();
    //6. Print search statistics
    Chatterbox.printStatistics(solver);

但我不明白我在哪里放置方程式。

Answer 1

是的，更确切地说，您应该将方程分解为几个约束：

10 < x < 100

变

solver.post(ICF.arithm(x,">",10));
solver.post(ICF.arithm(x,"<",100));

和

x*y + z + t - 10 = 0

变

// x*y = a 
IntVar a = VF.bounded("x*y",-25,25,solver);
solver.post(ICF.times(x,y,a); 
// a+z+t=10
IntVar cst = VF.fixed(10,solver);
solver.post(ICF.sum(new IntVar[]{a,z,t},cst)); 

最好，

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Answer 2

我之前没有使用过这个库，但也许您应该简单地将等式视为约束？