Line Jacobi (C Version)

#include 
#include 
# define N 52     /* for arrays with indices 0-51 in both dirs */


main()
{
double u[N][N],v[N][N],e[N][N];
double a[N],b[N],c[N],d[N],ratio;
double x,y,h,res,resmax,err,error;
int i,j,m,k;
double tol = .005;

/*
    Line Jacobi algorithm for Laplace Difference Equation 
*/


/*    Initialize  arrays and set boundary conditions  */

h = 1.0/N;
for(i=0;i0;j--)
    {
    d[j]=(d[j]-c[j]*d[j+1])/b[j];
    u[i][j] = d[j];
    }
  }  /* end for i (the last row)  */

/*  write u into v to prepare for the next iteration */

for(i=1;i resmax) resmax = fabs(res);
     err = e[i][j] - u[i][j];
     if(fabs(err) > error) error = fabs(err);
  }
}
printf("at iteration %d resmax = %f and error = %f\n",k,resmax,error);

}  /* end for k */
}  /* end main  */