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A_EhAb_AnD_gCd.cpp
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A_EhAb_AnD_gCd.cpp
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for (int k=0; k<N; k++)
{
// Initialize maximum value and index for pivot
int i_max = k;
int v_max = mat[i_max][k];
/* find greater amplitude for pivot if any */
for (int i = k+1; i < N; i++)
if (abs(mat[i][k]) > v_max)
v_max = mat[i][k], i_max = i;
/* if a prinicipal diagonal element is zero,
* it denotes that matrix is singular, and
* will lead to a division-by-zero later. */
if (!mat[k][i_max])
return k; // Matrix is singular
/* Swap the greatest value row with current row */
if (i_max != k)
swap_row(mat, k, i_max);
for (int i=k+1; i<N; i++)
{
/* factor f to set current row kth element to 0,
* and subsequently remaining kth column to 0 */
double f = mat[i][k]/mat[k][k];
/* subtract fth multiple of corresponding kth
row element*/
for (int j=k+1; j<=N; j++)
mat[i][j] -= mat[k][j]*f;
/* filling lower triangular matrix with zeros*/
mat[i][k] = 0;
}
//print(mat); //for matrix state
}