Forward Difference

//Forward Difference
x=input("Enter value of x as row matrix:")
y=input("Enter value of y as row matrix:")
xg=input("Enter xg at which we want to interpolate:")
n=length(x)
h=x(2)-x(1)
u=(xg-x(1))/h
disp("Forward difference table is:")
for i=1:n-1
    disp(diff(y,i))
end
yg=y(1)
p=u
for i=1:n-1
    d=diff(y,i)
    yg=yg+p*d(1)
    p=p*((u-i)/(i+1))
end
disp(yg,"The interpolation by forward difference table is :")

//Outputs
-->exec('D:\Scilab\Scilab without outputs\Forward difference.sce', -1)
Enter value of x as row matrix:[10 20 30 40 50]
Enter value of y as row matrix:[45 65 80 92 100]
Enter xg at which we want to interpolate:17

 Forward difference table is:  

    20.    15.    12.    8.

  - 5.  - 3.  - 4.

    2.  - 1.

  - 3.

 The interpolation by forward difference table is :  

    59.694488