Guass elimination method and guass column principal Element Elimination Method for Solving Linear Equations

# Include <stdio. h>
# Include <math. h>
# Include <conio. h>
# Define N 3
Void guass (double A [] [n + 1], double X [])
{
Double L [N];
Int I, J, K;
L [0] = 1.0;
For (I = 0; I <N-1; I ++)
{
If (FABS (A [I] [I]) <0.000001)
{
Printf ("cannot solve! /N ");
Return;
}
For (j = I + 1; j <n; j ++)
L [J] = A [J] [I]/A [I] [I];
For (j = I + 1; j <n; j ++)
For (k = I + 1; k <n + 1; k ++)
A [J] [k] = A [J] [k]-l [J] * A [I] [k];
} For (I = N-1; I> = 0; I --)
{
X [I] = A [I] [N];
For (j = I + 1; j <n; j ++) x [I] = x [I]-A [I] [J] * X [J];
X [I] = x [I]/A [I] [I];
}
}
Void main ()
{
Int I, J;
Double X [N];
Double S [N] [n + 1] ={{ 0.101, 2.304, 3.555, 1.183 },
{-1.347, 3.712, 4.623, 2.137 },
{-2.835, 1.072, 5.643, 3.035}
};
For (I = 0; I <n; I ++)
{
For (j = 0; j <= N; j ++) printf ("% 5.3f", s [I] [J]);
Printf ("/N ");
}
Guass (S, X );
For (I = 0; I <n; I ++) printf ("X [% d] = % 5.6f/N", I + 1, x [I]);
Getch ();
}/////////////////////////////////////// /// // # Include <stdio. h>
# Include <math. h>
# Include <conio. h>
# Define N 3
// Guass column principal element elimination method
Int guassl (double ** A, double * X, int N)
{
Int I, J, K, numl, * h, T;
Double * l, Max;
L = new double [N];
H = new int [N];
For (I = 0; I <n; I ++) H [I] = I; // row mark
For (I = 1; I <n; I ++)
{
Max = FABS (A [H [I-1] [I-1]);
Numl = I-1;
// Maximum value of column element
For (j = I; j <n; j ++)
{
If (FABS (A [H [J] [I-1])> MAX)
{
Numl = H [J];
Max = FABS (A [H [J] [I-1]);
}
}
If (max <0.00000000001) return 0;
// Exchange the row number
If (numl> i-1)
{
T = H [I];
H [I] = H [numl];
H [numl] = T;
}
For (j = I; j <n; j ++) L [J] = A [H [J] [I-1]/A [H [I-1] [I-1];
For (j = I; j <n; j ++)
For (k = I; k <n + 1; k ++) A [H [J] [k] = A [H [J] [k]-l [J] * A [H [I-1] [k];
}

For (I = n-1; I> = 0; I --)
{
X [H [I] = A [H [I] [N];
For (j = I + 1; j <n; j ++) X [H [I] = x [H [I]-A [H [I] [J] * X [H [J];
X [H [I] = x [H [I]/A [H [I] [I];
}
// Restore the value of X [I]
For (I = 0; I <n; I ++) L [I] = x [H [I];
For (I = 0; I <n; I ++) x [I] = L [I];
// Delete temporary array Variables
Delete [] L;
Delete [] h;
Return 1;
}
Void main ()
{
Int I, J;
Double X [N];
Double S [N] [n + 1] = {2, 8, 2, 14 },
{1, 6,-1, 13 },
{2,-1, 2, 5}
};
Double ** U;
U = new double * [N];
For (I = 0; I <n; I ++) U [I] = s [I];
For (I = 0; I <n; I ++)
{
For (j = 0; j <= N; j ++) printf ("% 5.3f", s [I] [J]);
Printf ("/N ");
}
Guassl (u, X, N );
For (I = 0; I <n; I ++) printf ("X [% d] = % 5.6f/N", I + 1, x [I]);
Delete [] U;
Getch ();
}