Java code Implementation----notes on matrix computing

Recently learning Hadoop, many algorithms need to use matrix computing, such as: collaborative filtering, PageRank, etc.

So practice a bit,

PUBLIC&NBSP;&NBSP;STATIC&NBSP;VOID&NBSP;M1 ()  {//  according to the rules of matrix multiplication, a[4 *3]  * b[3,2],//   will get a new matrix of r [4 *2]    //  r[i][j] = a[i][0] * b[0] [j] + //            a[i][1] *  b[1][j] +//            a[i][2] * b[ 2][j]int[][] a = new int[][] { { 1, 2, 3 }, { 4,  5, 6 }, { 7, 8, 9 },{ 1, 2, 3} };int [][]  b = new int[][]{{1,2},{3,4},{5,6} } ;int [][] r = new  int[4][2];int tmp =0;//  the number of columns,  The result set represents how many times the a  matrix needs to be traversed for  ( int k =0;  k < r[0].length; k++)  {//  double loop, traverse  a  matrix for  (int i =  0; i< a.length; i++ )  {tmp = 0;//  The result of each row, corresponding to an element in the result set for  (int j  = 0; j < a[0].length; j++)  {tmp += a[i][j] * b[j][k]  ;} R[i][k]=tmp;}} for  (int i = 0; i < r.length; i++)  {for  (int j  = 0; j < r[0].length; j++)  {system.out.print (r[i][j] +  "\ t");} System.out.println ();}}

This article from "Wandering Footsteps" blog, declined reprint!

Java code Implementation----notes on matrix computing