juzhengxiangcheng.txt

来自「计算两个矩阵相乘的源程序」· 文本 代码 · 共 40 行

#include <iostream>
using namespace std;
void MatMul(double *a, double *b, int m, int n, int k, double *c) 
{  
    int i,j,t,u;
    for (i=0;i<m;i++)
    for (j=0;j<k;j++)
    {     
       u=i*k+j;
       c[u]=0.0;
       for(t=0;t<n;t++)
       c[u]+=a[i*n+t]*b[t*k+j];
    }
}
int main()
{ 
   int i, j;
   double c[4][3];
   double a[4][5] = { { 1.05, 3.0, -2.0, 0.0, 4.0},
                      {-2.0, -1.0, 5.0, -7.0, 2.0},      
                      { 0.0, 8.0, 4.440, 1.0, -5.0},           
                      { 3.0, -3.24210, 2.0, -4.0, 1.0}};  
   double b[5][3] = { { 4.0, 5.0, -1.0},       
                      { 2.0, -2.0, 6.0},                 
                      { 7.0, 8.0, 1.0},                   
                      { 0.0, 3.02104, -5.0},                 
                      { 9.0, 8.0, -6.0}};
   MatMul(*a, *b, 4, 5, 3, *c); 
   for (i=0; i<4;i++)
      for (j=0;j<3;j++)
	  {
		  cout<<c[i][j]<<"   ";
		  if(j==2)
			  cout<<endl;
	  }
    
   return 0;
}