/// <summary> /// Adds the cap or floor option value. /// </summary> private static void AddOptionValue(Vector amount, OptionType optionType, Vector rate, double strike, Vector stdDev, double tau, double multiplier) { if (multiplier != 0.0 && tau > 0.0) { double optionStrike = 1.0 + tau * strike; amount.AddProduct(multiplier / tau, PricingFunctions.BlackFunction(optionType, rate, optionStrike, stdDev)); } }
/// <summary> /// Calculates the PV using analytic formula if at least one scenario needs it. /// </summary> private void CalculateAnalyticPV(Vector analyticPv, Vector isUnique, Vector[] stdDev, Vector yStar, Vector[] coefficient, Vector[] coupon, Vector dfTExpiry, Vector[] df) { if (isUnique.MaxElement() == 1.0) { OptionType optionType = fSwaptionDeal.Payer_Receiver == PayerReceiver.Payer ? OptionType.Call : OptionType.Put; // Value by summing the of the caplets or floorlets analyticPv.Clear(); using (var cache = Vector.CacheLike(yStar)) { // f_i(y*) plays the role of price and dfTPay[i] the strike. Vector optionletPrice = cache.Get(); VectorEngine.For(0, stdDev.Length, i => { // Performs optionletPrice = dfExpiry * fCoefficient[i] * Exp(-stdDev[i] * yStar) optionletPrice.Assign(CalcUtils.SafeExpMultiply(-stdDev[i] * yStar, coefficient[i] * dfTExpiry)); analyticPv.Add(coupon[i] * PricingFunctions.BlackFunction(optionType, optionletPrice, df[i], stdDev[i])); return(LoopAction.Continue); }); } } }
/// <summary> /// Calculate valuation profiles. /// </summary> public override void Value(ValuationResults valuationResults, PriceFactorList factors, BaseTimeGrid baseTimes) { PreValue(factors); TimeGridIterator tgi = new TimeGridIterator(fT); PVProfiles result = valuationResults.Profile; CashAccumulators cashAccumulators = valuationResults.Cash; BondOptionDeal deal = (BondOptionDeal)Deal; double baseDate = factors.BaseDate; double notional = deal.Notional; double interval = deal.Coupon_Interval; double buySign = (deal.Buy_Sell == BuySell.Buy) ? +1 : -1; double paySign = (deal.Option_Type == OptionType.Call) ? +1 : -1; double coupon = Percentage.PercentagePoint * deal.Coupon_Rate; double tExpiry = CalcUtils.DaysToYears(deal.Expiry_Date - baseDate); double tMaturity = CalcUtils.DaysToYears(deal.Bond_Maturity_Date - baseDate); IInterestYieldVol interestYieldVol = InterestVolBase.GetYieldVol(factors, deal.Yield_Volatility, fCurrency); if ((deal.Amortisation) != null && (deal.Amortisation.Count > 0)) { notional = deal.Amortisation.GetPrincipal(notional, deal.Expiry_Date); } bool respectDefault = Respect_Default == YesNo.Yes && fCreditRating != null; using (IntraValuationDiagnosticsHelper.StartDeal(fIntraValuationDiagnosticsWriter, Deal)) { using (var pricerCache = Vector.Cache(factors.NumScenarios)) { Vector defaultTime = null; Vector bondIsAlive = null; Vector historicalRecovery = null; if (respectDefault) { defaultTime = pricerCache.Get(); bondIsAlive = pricerCache.Get(1.0); historicalRecovery = pricerCache.GetClear(); fCreditRating.DefaultTime(defaultTime); } var defaultedBeforeBaseDate = respectDefault && CreditRating.DefaultedBeforeBaseDate(fCreditRating, baseDate); VectorEngine.For(tgi, () => { using (IntraValuationDiagnosticsHelper.StartValuation(fIntraValuationDiagnosticsWriter, tgi.Date)) { using (var cache = Vector.Cache(factors.NumScenarios)) { Vector optionValue = cache.GetClear(); Vector stdDev = cache.Get(); // Std.Dev of Price Vector stdDevYield = cache.Get(); //Std.Dev of Yield Vector price = cache.Get(); Vector yield = cache.Get(); Vector macaulayDuration = cache.Get(); Vector bondValue = cache.Get(); Vector df = cache.Get(); Vector dfr = fRepoIsDiscount ? null : cache.Get(); if (defaultedBeforeBaseDate) { result.AppendVector(tgi.Date, optionValue); return(LoopAction.Break); } // This BondPrice function returns the value of the bond cashflows after ExpiryDate, including accrual, discounted back to T.date double accrual, cash; PricingFunctions.BondPrice(bondValue, out accrual, out cash, baseDate, tgi.Date, deal.Expiry_Date, deal.Issue_Date, deal.Bond_Maturity_Date, notional, coupon, fPayDates, fAccruals, fDiscountRate, deal.Amortisation, fPrincipals, fFinalPrincipal, fSurvivalProb, +1.0); // Now check scenario by scenario for defaults, overwriting bondValue as necessary if (respectDefault) { AdjustBondValueForDefault(notional, tExpiry, bondValue, bondIsAlive, historicalRecovery, defaultTime, tgi.T, fDiscountRate, fRecoveryRate); } // convert price and duration to forward (tExpiry) basis if (tgi.Date == deal.Expiry_Date) { optionValue.Assign(buySign * VectorMath.Max(0.0, paySign * (bondValue - notional * fStrike))); cashAccumulators.Accumulate(fFxRate, tgi.Date, optionValue); } else { fDiscountRate.GetValue(df, tgi.T, tExpiry); if (fRepoIsDiscount) { dfr = df; } else { fRepoRate.GetValue(dfr, tgi.T, tExpiry); } // Need yield and duration to convert yield vol to price vol. PricingFunctions.BondForwardPriceAndAdjustedMacaulayDuration(price, macaulayDuration, tgi.T, tExpiry, tMaturity, coupon, interval, df, fDiscountRate, fSurvivalProb); PricingFunctions.BondYieldFromPrice(yield, tExpiry, tMaturity, coupon, interval, price); // Calculate Modified Duration from Macaulay Duration. Vector modifiedDuration = cache.GetClear(); PricingFunctions.GetModifiedDuration(modifiedDuration, macaulayDuration, yield, interval); // Calculate Std.Dev of Yield and Price interestYieldVol.GetStdDev(stdDevYield, tgi.T, yield, fStrikeYield, tExpiry, tMaturity - tExpiry); stdDev.Assign(modifiedDuration * stdDevYield); if (interestYieldVol.GetDistributionType() == ProbabilityDistribution.Lognormal) { stdDev.MultiplyBy(yield); } price.AssignQuotient(bondValue, df); PricingFunctions.BlackFunction(optionValue, deal.Option_Type, price, notional * fStrike, stdDev); optionValue.MultiplyBy(buySign * dfr); if (fIntraValuationDiagnosticsWriter.Level > IntraValuationDiagnosticsLevel.None) { // Add Intra-valuation Diagnostics using (var volatilitiesAtDateStore = IntraValuationDiagnosticsHelper.CreateVolatilitiesAtDateStore(fIntraValuationDiagnosticsWriter, factors.NumScenarios)) using (var volatilitiesYieldAtDateStore = IntraValuationDiagnosticsHelper.CreateVolatilitiesAtDateStore(fIntraValuationDiagnosticsWriter, factors.NumScenarios)) { volatilitiesAtDateStore.Add(tgi.Date, tgi.TimeGrid.fEndDate, stdDev); volatilitiesYieldAtDateStore.Add(tgi.Date, tgi.TimeGrid.fEndDate, stdDevYield); IntraValuationDiagnosticsHelper.AddBondOptionProperties(fIntraValuationDiagnosticsWriter, price, dfr, bondValue, accrual, volatilitiesAtDateStore, volatilitiesYieldAtDateStore); IntraValuationDiagnosticsHelper.AddCashflowsPV(fIntraValuationDiagnosticsWriter, optionValue); } } } result.AppendVector(tgi.Date, fFxRate.Get(tgi.T) * optionValue); return(LoopAction.Continue); } } }); } result.Complete(fT); } }