public void AdditionalPaymentTest()
{
Loan l = new Loan(3800000m, 0.12, new DateTime(2015, 1, 1), 120, Calendar.EmptyCalendar);
Assert.AreEqual(l.NumberOfPayments, 120);
Assert.IsTrue(Math.Abs(l.TotalPrincipalPayment - 3800000.0m) < Eps);
Assert.IsTrue(Math.Abs(l.TotalPayment - l.TotalPrincipalPayment - l.TotalInterest) < Eps);
l.AdditionalPayment(new DateTime(2015, 6, 1), 200000);
Assert.AreEqual(l.NumberOfPayments, 121);
Assert.IsTrue(Math.Abs(l.TotalPrincipalPayment - 3800000.0m) < Eps);
Assert.IsTrue(Math.Abs(l.TotalPayment - l.TotalPrincipalPayment - l.TotalInterest) < Eps);
}
public void LoanTest()
{
Loan l = new Loan(3800000m, 0.12, new DateTime(2015, 1, 1), 120, Calendar.EmptyCalendar);
Assert.AreEqual(l.NumberOfPayments, 120);
Assert.IsTrue(Math.Abs(l.TotalPrincipalPayment-3800000.0m) < Eps);
Assert.IsTrue(Math.Abs(l.TotalPayment - l.TotalPrincipalPayment - l.TotalInterest) < Eps);
Loan l1 = new Loan(521450.0m, 0.28, new DateTime(2015, 1, 25), 26, Calendar.EmptyCalendar); // RUS
Assert.AreEqual(l1.NumberOfPayments, 26);
Assert.IsTrue(Math.Abs(l1.TotalPrincipalPayment - 521450.0m) < Eps);
Assert.IsTrue(Math.Abs(l1.TotalPayment - l1.TotalPrincipalPayment - l1.TotalInterest) < Eps);
}
public void AdditionalPayment(DateTime date, decimal amount)
{
// todo: + percents for partial month
int i = 0;
for (; i < m_payments.Count; ++i)
if (m_payments[i].paymentDate > date)
break;
Debug.Assert(i > 0 && i < m_payments.Count);
decimal totalPaid = 0.0m;
for (int j = 0; j < i; ++j)
totalPaid += m_payments[j].principalPayment;
totalPaid += amount;
decimal newAmount = m_principal - totalPaid;
bool bHasFuturePayments = (i < m_payments.Count);
DateTime newStartDate = bHasFuturePayments ? m_payments[i + 1].paymentDate : date;
int newDuration = m_payments.Count - i;
m_payments.RemoveRange(i, newDuration);
m_payments.Add(new Cashflow(date, amount, 0.0m)); // todo: interest payments here
if (bHasFuturePayments)
{
Loan newLoan = new Loan(newAmount, m_rate, newStartDate, newDuration, m_calendar);
m_payments.AddRange(newLoan.Schedule);
m_payment = newLoan.Payment;
}
}