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-   -   Fast algorithm for computing matrix multiplication!!!! (http://www.go4expert.com/articles/fast-algorithm-computing-matrix-t8284/)

 asadullah.ansari 16Jan2008 16:49

Fast algorithm for computing matrix multiplication!!!!

Mostly people are using this algorithm to compute matrix multiplication:

Code: C

`#define n 1000int main(){    int a[n][n],b[n][n],c[n][n];    c[0][0]=0;    for( i=0;i<n;++i)    {        for(j=0;j<n;++j)        {            for(k=0;k<n;++k)            {                c[i][j] = c[i][j] + a[i][k] * b[k][j]            }        }    }    return 0;}`

In this program( a short algo) , every time we are taking one element of an array to catche and processing for it. Means At one time cpu reading one element value of a array and b Array and compute and store to c Array.

To reading every time elements from array , why we are taking some group of element i.e. Block size, then no need to read every element. A groups of element will be on catche and we can do fast as given above algo. This algorithm called " Block Algorithm". This Block algorithm can be applied many place where this type of situation will come.

Block Algorithm for Matrix Multiplication:
Code: C

`#define n 1000#define BlockSize  100int main(){    int a[n][n],b[n][n],c[n][n];    c[0][0]=0;    for( i1=0;i1<(n/BlockSize);++i1)    {        for(j1=0;j1<(n/BlockSize);++j1)        {            for(k1=0;k1<(n/BlockSize);++k1)            {                for(i=i1=0;i<min(i1+BlockSize-1);++i)                {                    for(j=j1=0;j<min(j1+BlockSize-1);++j)                    {                        for(k=k1;k<min(k1+BlockSize-1);++k)                        {                                           c[i][j] = c[i][j] + a[i][k] * b[k][j]                        }                    }                }            }        }           } return 0;}`

 debleena_doll2002 8Feb2008 09:40

Re: Fast algorithm for computing matrix multiplication!!!!

Yes!!! But can you tell me how's senario of Catche memory here?

 shabbir 8Feb2008 14:57

Re: Fast algorithm for computing matrix multiplication!!!!

Quote:
 Originally Posted by debleena_doll2002 Yes!!! But can you tell me how's senario of Catche memory here?
You can create a thread in the right category and it does not seem the right place.

 crazytolearn57 26Feb2008 18:40

Re: Fast algorithm for computing matrix multiplication!!!!

i didnt understand

 parvez.yu 27Feb2008 12:30

Re: Fast algorithm for computing matrix multiplication!!!!

nice

 aisha.ansari84 5Mar2008 18:18

Re: Fast algorithm for computing matrix multiplication!!!!

i feel its a reall nice way,good one

 alramesh 5Mar2008 20:15

Re: Fast algorithm for computing matrix multiplication!!!!

i m not getting at all.

 alramesh 5Mar2008 20:16

Re: Fast algorithm for computing matrix multiplication!!!!

Can you explain more about Block Algorithm?

 rahul.mca2001 6Mar2008 13:14

Re: Fast algorithm for computing matrix multiplication!!!!

Quote:
 Originally Posted by alramesh Can you explain more about Block Algorithm?
what is Block Algorithm

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