Name- Sayantan Mukherjee Roll No- 71
Newton’s Forward Difference Interpolation Program in C
Code:
#include <stdio.h>
#include<stdlib.h>
int fact(int n)
{
if(n==0 || n==1) return 1;
else return n*fact(n-1);
}
float r_prod(float r, int times)
{
if (times==0) return 1;
else {
times--;
return r*r_prod(r-1,times);
}
}
int main(int argc, char const *argv[])
{
int n;
float h,x,r,y;
printf("Enter n (the number of values provided): \n");
scanf("%d",&n);
float *arr_x=(float*) malloc(n*sizeof(float));
float *arr_y=(float*)malloc(n*sizeof(float));
printf("Enter %d values for x:\n",n);
for(int i=0;i<n;i++)
scanf("%f",&arr_x[i]);
printf("Enter %d values for y:\n",n);
for(int i=0;i<n;i++)
scanf("%f",&arr_y[i]);
printf("Enter the value of x to find:\n");
scanf("%f",&x);
if(x<arr_x[0] || x>arr_x[n-1])
{
printf("Value of x outside range.\n"); exit(0);}
else{
int **diff=(int**)malloc((n-1)*sizeof(int*));
for(int i=0;i<n-1;i++)
diff[i]=(int*) malloc ((n-1)*sizeof(int));
h=arr_x[1]-arr_x[0];
r= (x - arr_x[0])/h;
printf("Difference Table:\n");
//first difference
for(int i=0;i<n-1;i++)
{diff[i][0]=arr_y[i+1] - arr_y[i];
printf("%d ",diff[i][0] );}
