Need to Calculate the Inverse of A Matrix.

I need to calculate the Inverse of A matrix.
An nxn matrix using different row operations:

Row Interchange: Row i is interchanged with Row j in matrix A. We write Ri ↔ Rj .
Row Scaling: Row i in matrix A is multiplied by a nonzero scaling factor c. We write
Ri ← cRi.
Row Addition: Row i in matrix A is replaced by the sum of Row i and a multiple m of
some row Row j. We write Ri ← Ri + mRj .

I need help setting up the algorithm..
So i make a matrix B the Identity Matrix
And i have to make A into the identity matrix using various row operations.
and whatever i do to A i have to do to B to get the inverse

So far I have :

Code:

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#include<stdio.h>

void printMatrix (char name, double **matrix, int n)
{
    printf("%c =\n", name);
    int i,j;
    for (i=0; i<n; i++)
    {
        for (j=0; j<n; j++)
        {
            if (matrix[i][j] == -0.0)
                matrix[i][j] = 0.0;
            printf("  %11.4e", matrix[i][j]);
        }
        printf("\n");
    }
    return;
}

int main()
{

 
        int dimension;
        printf("Enter the dimension of square matrix: \n");
        scanf("%d",&dimension);
        printf("Enter the %d entries of the matrix:", dimension*dimension);
 
        scanf("%d %d", &dimension, &dimension);
        // allocate the first dimension (rows)
        int **matrix = (int **)malloc(dimension*sizeof(int *));

        // allocate the second dimension (columns)
        int i;
        for (i=0; i<dimension; i++)
        {
            matrix[i] = (int *)malloc(dimension*sizeof(int));
        }

       
        int k,l;
          for (k=0; k<M; k++)
          {
              for (l=0; l<N; l++)
              {
                  scanf("%lf",&table[k][l]);
              }
          }
         
          //Set up the identity Matrix
       
       
        int **matrixB = (int **)malloc(dimension*sizeof(int *));
        int j;
        for (j=0; j<dimension; j++)
        {
            matrixB[i] = (int *)malloc(dimension*sizeof(int));

      }
          //Make B the identity Matirix.
        int m,n;
        for(m=0;m<=dimension;m++)
        {
                        for(n=0;n<=dimension;n++)
                        {
                        if(m==n)
                        matrixB[m][m]=1;
                        else
                        matrixB[m][n]=0;
                        }
        }
       
}

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Do the names Gauss and Jordan mean anything to you?

How do i do a function for the gaussian elimination

You start at the beginning, and keep going until you get to the end. What do you mean, how do you do a function?

Use Google --- tons of stuff out there!!

What do you mean start at the beginning and finish at the end? I dont know how to write the function. if i knew i wud not ask you tabstop.
Thanks Kcpilot i looked on google but was very confused..

Quoting the algorithm from Wikipedia:

Quote:

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Code:

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i := 1
j := 1
while (i ≤ m and j ≤ n) do
  Find pivot in column j, starting in row i:
  maxi := i
  for k := i+1 to m do
    if abs(A[k,j]) > abs(A[maxi,j]) then
      maxi := k
    end if
  end for
  if A[maxi,j] ≠ 0 then
    swap rows i and maxi, but do not change the value of i
    Now A[i,j] will contain the old value of A[maxi,j].
    divide each entry in row i by A[i,j]
    Now A[i,j] will have the value 1.
    for u := i+1 to m do
      subtract A[u,j] * row i from row u
      Now A[u,j] will be 0, since A[u,j] - A[i,j] * A[u,j] = A[u,j] - 1 * A[u,j] = 0.
    end for
    i := i + 1
  end if
  j := j + 1
end while

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You start at the beginning of the algorithm and you go to the end. (Actually, this is Gaussian elimination, not Gauss-Jordan, but it should get you started.)