Java IloCplex.exportModel方法代码示例

import ilog.cplex.IloCplex; //导入方法依赖的package包/类
public void exportToDisk(IMIP mip, Path path) {
    try {
        IloCplex cplex = CPLEXInstanceManager.INSTANCE.checkOutCplex();

        setControlParams(cplex, mip.getSpecifiedSolveParams(),mip::getSolveParam);
        Map<String, IloNumVar> vars = setupVariables(mip, cplex);
        setupConstraints(mip, cplex, vars);

        setUpObjective(mip, cplex, vars);
        cplex.exportModel(path.toString());
    } catch (Exception ex) {
        logger.error("Failed to write cplex model to disk", ex);
    }

}
 

import ilog.cplex.IloCplex; //导入方法依赖的package包/类
public IMIPResult solve(IMIP mip) throws MIPException {
    IloCplex cplex = CPLEXInstanceManager.INSTANCE.checkOutCplex();
    try {
        // This blocks until one can be obtained:
        while (cplex.getObjective() != null) {
            CPLEXInstanceManager.INSTANCE.checkInCplex(cplex);
            logger.warn("Model not cleared");
            cplex = CPLEXInstanceManager.INSTANCE.checkOutCplex();
        }

        logger.debug("About to set parameters... ");

        setControlParams(cplex, mip.getSpecifiedSolveParams(), mip::getSolveParam);

        // Log only on info logging level
        if (!mip.getBooleanSolveParam(SolveParam.DISPLAY_OUTPUT, false) && !logger.isDebugEnabled()) {
            cplex.setParam((IntParam) getCplexParam(SolveParam.MIP_DISPLAY), 0);
        }

        // cplex.setParam(IloCplex.DoubleParam.EpInt,
        // 1.0/(MIP.MAX_VALUE*1.0-1));
        // cplex.setParam(IloCplex.DoubleParam.EpRHS,
        // 1.0/(MIP.MAX_VALUE*1.0-1));

        long convertStartTime = System.currentTimeMillis();
        logger.debug("Starting to convert mip to Cplex object.");

        Map<String, IloNumVar> vars = setupVariables(mip, cplex);
        Map<Constraint, IloRange> constraintsToIloConstraints = setupConstraints(mip, cplex, vars);

        setUpObjective(mip, cplex, vars);

        logger.debug("Converting mip done. Took: " + (System.currentTimeMillis() - convertStartTime) + " ms");

        // write model to file for debugging:
        // ///////////////////////////////////

        String fileName = mip.getStringSolveParam(SolveParam.PROBLEM_FILE, new String("mipInstance"));
        if (!fileName.equals("")) {
            cplex.exportModel(/* "" + */fileName + ".lp");// + ".txt");
        }

        return solveMip(mip, cplex, vars, constraintsToIloConstraints);
    } catch (IloException e) {
        if (mip.getBooleanSolveParam(SolveParam.DISPLAY_OUTPUT, true)) {
            e.printStackTrace();
        }
        throw new MIPException("Cplex Exception: " + e.toString());
    } catch (RuntimeException ex) {
        if (mip.getBooleanSolveParam(SolveParam.DISPLAY_OUTPUT, true)) {
            ex.printStackTrace();
        }
        throw ex;
    } finally {
        CPLEXInstanceManager.INSTANCE.checkInCplex(cplex);
    }
}
 

import ilog.cplex.IloCplex; //导入方法依赖的package包/类
public static void main(String[] args) throws IloException {
    //Define cplex reponsavel por criar variáveis e seus limites, definir restrições, parâmetros e resolver o modelo. 
    IloCplex cplex = new IloCplex();
    
    //Definindo as 3 variáveis do problema no intervalo de 0 até infinito e do tipo Float
    IloNumVar x[] = cplex.numVarArray(3, 0, Double.POSITIVE_INFINITY, IloNumVarType.Float);
    
    //Mundando limite superior (ub - upper bound) da variável x1 como 5
    x[0].setUB(5);
    
    //Definindo expressão para a função objetivo
    IloNumExpr objective = cplex.prod(0.5, x[0]);
    objective = cplex.sum(objective, cplex.prod(4, x[1])); 
    objective = cplex.sum(objective, cplex.prod(7, x[2])); 
    //Adiciona ao cplex a expressão do objetivo como problema de maximização
    cplex.addMaximize(objective);
    
    //Definnindo a expressão para a primeira restrição do problema
    IloNumExpr restriction1 = cplex.prod(7, x[0]);
    restriction1 = cplex.sum(restriction1, cplex.prod(-3, x[1])); 
    restriction1 = cplex.sum(restriction1, cplex.prod(0.5, x[2]));
    //Adiciona ao cplex a restrição como maior ou igual a 10
    cplex.addGe(restriction1, 10);
    
    //Definnindo a expressão para a segunda restrição do problema
    IloNumExpr restriction2 = cplex.prod(2, x[1]);
    restriction2 = cplex.sum(restriction2, cplex.prod(5, x[2])); 
    //Adiciona ao cplex a restrição como menor ou igual a 80
    cplex.addLe(restriction2, 80);
    
    cplex.exportModel("model.lp"); 
    
    if(cplex.solve()){
        System.out.println("O modelo possui solução");
        System.out.println("Status: "+cplex.getStatus());
        
        double obj = cplex.getObjValue();
        System.out.println("objetivo = "+obj);
        
        double sol[] = cplex.getValues(x);
        System.out.println("x1 = "+sol[0]);
        System.out.println("x2 = "+sol[1]);
        System.out.println("x2 = "+sol[2]);
        
    }else{
        System.out.println("O modelo não possui solução");
        System.out.println("Status: "+cplex.getStatus());
    }
}