calcul simplifié (probablement faux) d'un tableau d'amortissement

amortissement_pret_bacnaire.py

import sys

def annuite(interest_rate, years, capital):
    return (capital * interest_rate)/(1 - (1+interest_rate)**-years)

def tableau_amortissement(years, capital, interest_rate):
    a = float(format(annuite(interest_rate, years, capital), '.2f'))
    capital_debut_periode = capital
    print("Annuité du prêt: " + str(a))
    for i in range(years):
        ip = interest_rate * capital_debut_periode
        capital_amorti = a - i
        print("ANNEE N"+str(i+1)+":")
        print("capital du en début de période: " + str(capital_debut_periode))
        print("intérêts payés: "+ str(ip))
        print("capital amorti: " + str(a - ip))
        capital_debut_periode -= capital_amorti

print(sys.argv)
years = int(sys.argv[1])
capital = float(sys.argv[2])
interest_rate = float(sys.argv[3])
tableau_amortissement(years, capital, interest_rate)