java ORTools/SCIP如何使用指标约束解决MIP问题？

Question

Minizing站点（https://www.minizinc.org/doc-2.5.5/en/solvers.html#indicator-constraints）声明MIP SCIP解算器支持指标约束

我在http://google.github.io/or-tools/javadoc/com/google/ortools/linearsolver/MPIndicatorConstraint.html找到了MPIndicatorConstraint文档，但没有相关的示例

C++文档还通知了一个MPoServer接口，它有一个AddiaDeaCuffor方法，在java文档中（https://developers.google.com/optimization/reference/linear_solver/linear_solver/MPSolverInterface?hl=en）

中没有发现并行的方法。

CP模型的一些示例可以在https://github.com/google/or-tools/blob/master/ortools/sat/doc/channeling.md#java-code上找到，但我找不到任何与MIP相关的类似应用程序

有没有记录过任何例子？如果没有，是否可以在此线程上共享一个

Answer 1

根据这个test case应该可以通过使用proto接口构建模型来使用指标约束。是否有将其移植到MPSolver的路线图

    @Test
    public void shouldSolveLPWithIndicatorConstraint() {
        final MPModelProto.Builder mpModelProto = this.getLinearObjective();

        final MPVariableProto k = this.getIntVar("k").setUpperBound(1.0d).build();
        mpModelProto
                .addVariable(2, k)
                .removeConstraint(0);

        // x + 7y <= 17.5
        final MPConstraintProto c0_0 = this.getFirstConstraint(17.5d);
        // x + 7y <= 24.5
        final MPConstraintProto c0_1 = this.getFirstConstraint(24.5d);

        final MPIndicatorConstraint ic0 = MPIndicatorConstraint.newBuilder()
                .setVarIndex(2)
                .setVarValue(0)
                .setConstraint(c0_0)
                .build();

        final MPIndicatorConstraint ic1 = MPIndicatorConstraint.newBuilder()
                .setVarIndex(2)
                .setVarValue(1)
                .setConstraint(c0_1)
                .build();

        mpModelProto
                .addGeneralConstraint(MPGeneralConstraintProto.newBuilder().setIndicatorConstraint(ic0).build())
                .addGeneralConstraint(MPGeneralConstraintProto.newBuilder().setIndicatorConstraint(ic1).build());

        final MPSolutionResponse mpSolutionResponse = this.solve(mpModelProto);

        assertEquals(MPSOLVER_OPTIMAL, mpSolutionResponse.getStatus());
        assertEquals(33.0d, mpSolutionResponse.getObjectiveValue());
        assertEquals(3.0d, mpSolutionResponse.getVariableValue(0));
        assertEquals(3.0d, mpSolutionResponse.getVariableValue(1));
        assertEquals(1.0d, mpSolutionResponse.getVariableValue(2));
    }