[Tutor] I Need Help

[Micheal Emeagi]

Hello Tutor,

I am a newbie programmer trying to implement  an exponential smoothing
forcast using two list. Yt list has the Y values and Ft list has the
forcast values. Ft is the forcast list whose length should be one element
greater than the Yt list. I want the elements of ft to increment by one
while I use it to generate the subsequent element. But for some reasons I
don't understand, it keeps changing the second element in Ft.

Could please help me figure what is going wrong with the while iteration.
See below the code.

Michael



yt = [1,2,3,4,5,6]

ft = [yt[0],yt[0]]
alpha = 0.5
while len(ft) != len(yt) + 1:

    ft.append(ft[1] + alpha * (yt[1] - ft[1]))

    print(ft)
    ft[1] += 1
    yt[1] += 1
print (ft)