import QuantLib as ql # 1. Set the global evaluation date calc_date = ql.Date(15, 6, 2026) ql.Settings.instance().evaluationDate = calc_date # 2. Define the yield curve (flat rate of 4.5% for this example) rate = ql.SimpleQuote(0.045) day_counter = ql.Actual365Fixed() interest_rate = ql.InterestRate(rate.value(), day_counter, ql.Compounded, ql.Annual) yield_curve = ql.FlatForward(0, ql.NullCalendar(), ql.QuoteHandle(rate), day_counter) discount_curve = ql.YieldTermStructureHandle(yield_curve) # 3. Create a list of cash flows with specific amounts and payment dates dates = [ql.Date(15, 6, 2027), ql.Date(15, 6, 2028), ql.Date(15, 6, 2029)] amounts = [100.0, 150.0, 200.0] leg = [ql.SimpleCashFlow(amount, d) for amount, d in zip(amounts, d)] # 4. Calculate Net Present Value include_today = False npv = ql.CashFlows.npv(leg, discount_curve, include_today) print(f"The Present Value is: {npv:.4f}")