java - Java 中用于矩阵乘法的数学运算符

Question

您好，我对 Java 编码相当陌生，因此请原谅任何愚蠢的错误或问题。我从一些互联网来源获得了这段代码，该代码将两个矩阵相乘并用 Java 给出结果。我已对其进行编辑以供自己使用。代码如下:

 for ( c = 0 ; c < 3 ; c++ )
         {
            for ( d = 0 ; d < 1 ; d++ )
            {   
               for ( int k = 0 ; k < 3 ; k++ )
               {
                  Math.sum = sum + transformation[c][k]*sub[k][d];
               }

               multiply[c][d] = sum;
               sum = 0;
            }
         }

         System.out.println("Product of entered matrices:-");

         for ( c = 0 ; c < 3 ; c++ )
         {
            for ( d = 0 ; d < 1 ; d++ )
               System.out.print(multiply[c][d]+"\t");

            System.out.print("\n");
         }

所以现在我在总和和乘法下看到红线，说“总和无法解析或不是字段”和“乘法无法解析为变量”。谁能解释一下错误的原因以及如何解决它。谢谢

Answer 1

公共(public)类乘法{

public static void main(String[] args) {
    int rows=3, columns=3;
    double multiply[][] = new double[rows][columns]; // product of transformation X sub
    double matA[][] = { { 2, 3, 6 }, { 1, 4, 6 }, { 4, 1, 3 } },
       matB[][] =  { { 2, 1, 0 }, { 3, 5, 1 }, { 3, 2, 1 } }, 
       sum;

    for (int k = 0; k < columns; k++) {
        for (int c = 0; c < rows; c++) {
            sum = 0;
            for (int d = 0; d < columns; d++) {
                sum = sum + matA[c][d] * matB[d][k];
            }
            multiply[c][k] = sum;
        }
    }
    System.out.println("Product of Matrix A & B matrices:-");
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < columns; j++)
            System.out.print(multiply[i][j] + "\t");
        System.out.print("\n");
    }
}

}