模擬分期付款（II）

你決定在上一題的程式基礎上擴充功能，將每期支付的本金與利息都存起來，並改成繪圖呈現結果，而不是只印出數值。

在這個例子中，繪圖的程式碼已經寫好了，所以你只需要完成 for 迴圈內的邏輯，以及每次迭代會更新的變數初始化。

本練習屬於課程

Python 金融概念入門

檢視課程

練習說明

將每一期的 interest_paid 與 principal_paid 儲存起來。
根據本金償還金額與剩餘本金，計算每一期的 principal_remaining。
執行提供的程式碼，繪製每月利息與本金支付的比較圖。

動手互動練習

試著完成這個範例程式碼，體驗一下這個練習。

# Loop through each mortgage payment period
for i in range(0, mortgage_payment_periods):
    
    # Handle the case for the first iteration
    if i == 0:
        previous_principal_remaining = mortgage_loan
    else:
        previous_principal_remaining = principal_remaining[i-1]
        
    # Calculate the interest based on the previous principal
    interest_payment = round(previous_principal_remaining*mortgage_rate_periodic, 2)
    principal_payment = round(periodic_mortgage_payment - interest_payment, 2)
    
    # Catch the case where all principal is paid off in the final period
    if previous_principal_remaining - principal_payment < 0:
        principal_payment = previous_principal_remaining
        
    # Collect the historical values
    interest_paid[i] = ____
    principal_paid[i] = ____
    principal_remaining[i] = ____
    
# Plot the interest vs principal
plt.plot(interest_paid, color="red")
plt.plot(principal_paid, color="blue")
plt.legend(handles=[interest_plot, principal_plot], loc=2)
plt.show()

編輯並執行程式碼