java 简单矩阵乘法运算

2.第一个矩阵的行数决定了结果矩阵的行数，第二个矩阵的列数决定了结果矩阵的列数；

 1 package org.admln.matrix;
 2 /*
 3  * 20150211
 4  */
 5 public class MatrixMultiplication {
 6     public static void main(String[] args) {
 7         /*
 8          * 1.构建矩阵
 9          *              2 9 7               4 2
10          *    matrix1= 3 1 4      matrix2= 6 8
11          *                                 2 6
12          */
13         int[][] matrix1 = {{2,9,7},{3,1,4}};
14         int[][] matrix2 = {{4,2},{6,8},{2,6}};
15         System.out.println("matrix1矩阵为" + matrix1.length + "行" + matrix1[0].length +"列");
16         for(int i=0;i<matrix1.length;i++) {
17             for(int j=0;j<matrix1[i].length;j++) {
18                 System.out.print("\t" + matrix1[i][j]);
19             }
20             System.out.println();
21         }
22         System.out.println("matrix2矩阵为" + matrix2.length + "行" + matrix2[0].length +"列");
23         for(int i=0;i<matrix2.length;i++) {
24             for(int j=0;j<matrix2[i].length;j++) {
25                 System.out.print("\t" + matrix2[i][j]);
26             }
27             System.out.println();
28         }
29         /*
30          * 2.矩阵相乘
31          */
32         System.out.println("结果矩阵为" + matrix1.length + "行" + matrix2[0].length + "列");
33         for(int i=0;i<matrix1.length;i++) {
34             for(int j=0;j<matrix2[0].length;j++) {
35                 int sum = 0;
36                 for(int k=0;k<matrix2.length;k++) {
37                     sum += matrix1[i][k] * matrix2[k][j];
38                 }
39                 System.out.print("\t" + sum);
40             }
41             System.out.println();
42         }
43     }
44 }