how can I create graphics using matplotlib

[Gribouillis]

I could run your code in Scilab. Here is a first python equivalent

import numpy as np
from matplotlib import pyplot as plt
N = 40
x = np.ones(N+1)
b = 0.7
S = 5
a =(1 - b) / (1-b**S)
i = np.arange(1,S+1)
 
w = a * (b**(S-i))
# print(w)
y = np.zeros(N)
y[S-1:] = [ np.dot(w, x[n-S+1:n+1].T) for n in range(S-1, N)]
print(y)
print(len(y))
plt.plot(range(S, N+1),y[S-1:], marker='o')
plt.plot(range(S, N+1),y[S-1:], linestyle='-')
plt.show()