一：cplex的使用：
1.1 匯入cplex.jar,包的地址：https://pan.baidu.com/s/1Q0Bv24EQdelV2rY-IrLoZQ 提取碼：xn14
1.2 將cplex1290.dll （地址：https://pan.baidu.com/s/1sQXqYTSJWywwaZt5AHVkZQ 提取碼：nm0l）添加到VM option中，這里以IDEA為例，
同樣eclipse
**二、求解問題，
- 一個簡單的線性規劃問題：**
maxs.t.x1+2x2+3x3
?x1+x2+x3≤20
x1?3x2+x3≤30
0≤x1≤40
java 中的 cplex 代碼如下：
import ilog.concert.IloException;
import ilog.concert.IloNumVar;
import ilog.cplex.IloCplex;
public class LP1 {
public static void main(String[] args) {
try {
IloCplex cplex = new IloCplex(); // creat a model
double[] lb = {0.0, 0.0, 0.0};
double[] ub = {40.0, Double.MAX_VALUE, Double.MAX_VALUE};
IloNumVar[] x = cplex.numVarArray(3, lb, ub);
double[] objvals = {1.0, 2.0, 3.0};
cplex.addMaximize(cplex.scalProd(x, objvals));
double[] coeff1 = {-1.0, 1.0, 1.0};
double[] coeff2 = {1.0, -3.0, 1.0};
cplex.addLe(cplex.scalProd(x, coeff1), 20.0);
cplex.addLe(cplex.scalProd(x, coeff2), 30.0);
if (cplex.solve()) {
cplex.output().println("Solution status = " + cplex.getStatus());
cplex.output().println("Solution value = "https://blog.csdn.net/hyy_blue/article/details/+ cplex.getObjValue());
double[] val = cplex.getValues(x);
for (int j = 0; j < val.length; j++)
cplex.output().println("x" + (j+1) + " = " + val[j]);
}
cplex.end();
} catch (IloException e) {
System.err.println("Concert exception caught: " + e);
}
}
}
輸出結果：
Tried aggregator 1 time.
N
o LP presolve or aggregator reductions.
Presolve time = 0.00 sec. (0.00 ticks)
Iteration log . . .
Iteration: 1 Dual infeasibility = 0.000000
Iteration: 2 Dual objective = 202.500000
Solution status = Optimal
Solution value = https://blog.csdn.net/hyy_blue/article/details/202.5
x1 = 40.0
x2 = 17.5
x3 = 42.5
這里注意一下，求的是線性公式的最大值，而在MATLAB中利用x=linprog(f,[],[],Aeq,beq,lb);求解的是最小值（我怎么除錯都不一致的原因），這里的引數就不在贅述了，
還有就是設定cplex API在https://wenku.baidu.com/view/7095dd76777f5acfa1c7aa00b52acfc789eb9fed.html有介紹（雖然是c#的，但是java可以借鑒，
三 線性最優解的java實作
代碼地址：https://pan.baidu.com/s/1UeyQdPLMideXKqUaDBFYZQ 提取碼：rte1
里面有詳細注解，這里就不再解釋，希望對大家有幫助！
借鑒：https://blog.csdn.net/robert_chen1988/article/details/78678289 ，感謝這位博主的文章，
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標籤：其他