Java实现熵值法计算权重示例
时间: 2023-05-19 10:06:23 浏览: 86
以下是 Java 实现熵值法计算权重的示例代码:
```
import java.util.ArrayList;
import java.util.List;
public class EntropyWeight {
public static void main(String[] args) {
// 初始化数据
double[][] data = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
// 计算熵值权重
double[] weight = entropyWeight(data);
// 输出结果
for (double w : weight) {
System.out.println(w);
}
}
/**
* 计算熵值权重
*
* @param data 数据矩阵
* @return 权重数组
*/
public static double[] entropyWeight(double[][] data) {
int row = data.length;
int col = data[0].length;
// 归一化矩阵
double[][] normData = new double[row][col];
for (int j = 0; j < col; j++) {
double sum = 0;
for (int i = 0; i < row; i++) {
sum += data[i][j];
}
for (int i = 0; i < row; i++) {
normData[i][j] = data[i][j] / sum;
}
}
// 计算熵值
double[] entropy = new double[col];
for (int j = 0; j < col; j++) {
double sum = 0;
for (int i = 0; i < row; i++) {
sum += normData[i][j] * Math.log(normData[i][j]);
}
entropy[j] = -sum / Math.log(row);
}
// 计算权重
double[] weight = new double[col];
double sum = 0;
for (int j = 0; j < col; j++) {
weight[j] = 1 - entropy[j];
sum += weight[j];
}
for (int j = 0; j < col; j++) {
weight[j] /= sum;
}
return weight;
}
}
```
这段代码实现了熵值法计算权重的过程,首先对数据矩阵进行归一化处理,然后计算每个指标的熵值,最后根据熵值计算权重。