java第五次上机实验

} } double [][]m = newdouble [3][4]; System.out.println(\输入3 * 4矩阵: \); Scanner reader = new Scanner(System.in); for(inti = 0; i< 3; i ++) for(intj = 0; j< 4; j++) { } //m[i][j] = 2.0;// m[i][j] = reader.nextDouble(); Array a = new Array(); System.out.println(\矩阵第一列元素之和:\+ a.sumColumn(m,1));

运行结果:

五、编写两个矩阵相乘的方法。方法头如下：

public static double[][] multiplyMatrix(double[][] a ,double[][] b) 编写程序进行测试。

实验代码: import java.util.Scanner; class Array{ } publicclass Project5 { /** * @param args */ publicstaticvoid main(String[] args) { publicstaticdouble[][] multiplyMatrix(double[][] a ,double[][] b){ } doubletemp[][] = newdouble[3][3]; doublesum = 0; for(inti = 0; i< 3; i ++){ } for(intj = 0; j< 3; j++){ } sum = 0; for(intp = 0; p< 3; p++) sum += a[i][p] * b[p][j]; temp[i][j] = sum; returntemp; // TODO Auto-generated method stub doublea[][] = newdouble [3][3]; doubleb[][] = newdouble [3][3]; doublec[][] = newdouble [3][3]; Scanner reader = new Scanner(System.in); System.out.println(\输入矩阵a:\); for(inti = 0; i< 3; i++) for(intj = 0; j< 3; j++){ } a[i][j] = reader.nextDouble(); System.out.println(\输入矩阵b:\); for(inti = 0; i< 3; i++) for(intj = 0; j< 3; j++){ } b[i][j] = reader.nextDouble(); Array d = new Array(); c = d.multiplyMatrix(a, b); for(inti = 0; i< 3; i++){ } for(intj = 0; j< 3; j++) System.out.print(c[i][j] +\); System.out.print('\\n'); } }

运行结果：