- Hi,

I am writing a java program to factor large number and I was just

wondering if anyone can help me by checking if the code below does

the gaussian row reduction correctly.

public void gaussian_elim(int[][] matrix, int rows, int cols)

{

int i, j, k, t, nonzero_row, nonzero_col, next_row = 0, piv_row = 0;

int[] row1 = new int[cols];

for (i = 0; i < cols; i++)

{

for (j = next_row; j < rows; j++)

{

if (matrix[j][i] == 1)

{

nonzero_col = i;

nonzero_row = j;

System.arraycopy(matrix[nonzero_row], 0, row1, 0,cols);

System.arraycopy(matrix[next_row], 0, matrix

[nonzero_row], 0, cols);

System.arraycopy(row1, 0, matrix[next_row], 0, cols);

for (k = nonzero_row + 1; k < rows; k++)

{

if (matrix[k][nonzero_col] == 1)

{

for (t = 0; t < cols; t++)

{

matrix[k][t] = matrix[k][t] ^ matrix[next_row]

[t];

}

}

}

next_row++;

j = rows;

}

}

}

for (i = 0; i < rows; i++)

{

for (j = i+1; j < cols; j++)

{

if(j < rows)

piv_row = j;

if (matrix[i][j] == 1)

{

matrix[i][j] = matrix[i][j] ^ matrix[piv_row]

[j];

}

}

}

for(i = 0; i < rows; i++){

for(j = 0; j < cols; j++)

System.out.print(matrix[i][j]);

System.out.println(" ");

}

}

Thanks for your time and help.

-VJ - --- In primenumbers@yahoogroups.com, "vijaysomu" <vijaysomu@y...>
> I am writing a java program to factor large number

Are you aware of Dario Alejandro Alpern's Java Factoring program? It

does algebraic factorization, then Cunningham Lookup, then trial

factorization, then ECM, and finally, for sufficiently small numbers,

finishes with SIQS. He's been optimizing the code, so it's fast. It

handles numbers up to 10,000 digits.

http://www.alpertron.com.ar/ECM.HTM

--

===========================================================

ElevenSmooth: Distributed Factoring of 2^3326400-1

http://www.mersenneforum.org/elevensmooth - Hi,

Thats true but I am writing this as part of my course work and I am

supposed to implement Dixon's Quadratic Sieve.

Thanks,

-VJ

--- In primenumbers@yahoogroups.com, "elevensmooth"

<elevensmooth@y...> wrote:> --- In primenumbers@yahoogroups.com, "vijaysomu" <vijaysomu@y...>

It

> > I am writing a java program to factor large number

>

> Are you aware of Dario Alejandro Alpern's Java Factoring program?

> does algebraic factorization, then Cunningham Lookup, then trial

numbers,

> factorization, then ECM, and finally, for sufficiently small

> finishes with SIQS. He's been optimizing the code, so it's fast.

It

> handles numbers up to 10,000 digits.

>

> http://www.alpertron.com.ar/ECM.HTM

>

> --

> ===========================================================

> ElevenSmooth: Distributed Factoring of 2^3326400-1

> http://www.mersenneforum.org/elevensmooth