Function calculate_amortization_payment

calculate_amortization_payment(
    principal: number,
    apr: number,
    months: number,
    fixed_payment?: number,
    digits?: number,
): Readonly<AmortizationPayment>
Calculates the payment, interest portion of that payment, principal portion of that payment, and remaining balance after that payment of an amortization loan
Parameters
- principal: number
  the starting principal of the loan
- apr: number
  the interest rate of the loan
- months: number
  the number of months for the loan
- Optionalfixed_payment: number
  if provided, uses a fixed monthly payment amount. This is useful for mortgage-style calculations wherein the monthly payment remains the same for the length of the loan. This differs from something like a revolving credit balance where the payment can change every month.
- digits: number = 2
  the number of digits to round the result to
Returns Readonly<AmortizationPayment>