I have been given a task to create an interpolating/extrapolating programme. I have completed the programme for linear interpolation (2 points) but now must make it usable for 3 or more points, ie a polynomial of n points. I think I have the equation in general for a polynomial as it is an infinite series up to nth degree and have tweaked the general formula of summation. So far I have;(adsbygoogle = window.adsbygoogle || []).push({});

n= int(input("How many data points do you have for the polynomial="))for d in range (1, n+1):

x = float(input ("Enter 1st x value x"))

y = float(input ("Enter 1st y value y"))

yi =0e0for i in range (1, n+1):

p=1e0for j in range (1, n+1):if(j != i):

p *=(xi-x[j])/(x-x[j])

yi += p*y

print(yi)

but I need a way of having the user input the number of coordinates they have (n) and then using this information, the points they input take up the role of x[1] y[1]... up to x[n+1] and y[n+1] but I don't have a clue how to do this. I should probably mention we are not aloud to use .scipy or such add ons, we must do it all from scratch.

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# Python How can I input a polynomial equation of infinite terms in P

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