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Which order of loops is fastest in matrix multiplication and why ?

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for(i=0;i<n;i++)
  for(j=0;j<n;j++)
     for(k=0;k<n;k++)
        C[i][j]+=A[i][k]*B[k][j];

In this algorithm, there are 6 combinations of loops : the one given above is ijk. The others are ikj,jki,jik,kij and kji. Which one executes the fastest and why?

posted Jun 29, 2016 by anonymous

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