C Program for Gauss Elimination Method

Program #include<stdio.h> #include<conio.h> void main() { int n,i,j,dum; float a[10][10],k,sum,x[10]; clrscr(); printf...

Program

#include<stdio.h>
#include<conio.h>
void main()
{
int n,i,j,dum;
float a[10][10],k,sum,x[10];
clrscr();
printf("\n Enter the no of equation or unkown = ");
scanf("%d",&n);
printf("\n Enter the element of augmented matrix");
for(i=1;i<=n;i++)
{
for(j=1;j<=n+1;j++)
{

printf("\n Enter the element a[%d][%d]= ",i,j);
scanf("%f",&a[i][j]);
}
}
printf("\n The Enter augmented matrix is");
for(i=1;i<=n;i++)
{
printf("\n");
for(j=1;j<=n+1;j++)
{
printf("% 0.2f\t",a[i][j]);
}}
//Triangularisation begins from here
for(dum=1;dum<=n-1;dum++)
{
for(i=dum;i<=n-1;i++)
{
k=a[i+1][dum]/a[dum][dum];
for(j=dum;j<=n+1;j++)
{
a[i+1][j]-=(k*a[dum][j]);
}
}
}
/*printf("\n The triangularised augmented matrix");
for(i=1;i<=n;i++)
{
printf("\n");
for(j=1;j<=n+1;j++)
{
printf("\n % 2f/t",a[i][j]);
}
} */
//Backward substitution begins from here
for (i=n;i>0;i--)
{
sum=0;
for(j=n;j>0;j--)
{
if(j>i)
{
sum+=(a[i][j]*x[j]);
}
else
{
x[i]=(a[i][n+1]-sum)/a[i][j];
break;
}}}
//The output begins from here
printf("\n The calculation of the given system of liner equation is");
for(i=1;i<=n;i++)
{
printf("\n x[%d]=%2f",i,x[i]);
}
getch();
}

Output