/// <summary>
/// Prepare for valuation anything that is not dependent upon the scenario.
/// </summary>
public override void PreCloneInitialize(PriceFactorList Factors, BaseTimeGrid BaseTimes, RequiredResults ResultsRequired)
{
base.PreCloneInitialize(Factors, BaseTimes, ResultsRequired);
DealCreditLinkedNoteBase deal = (DealCreditLinkedNoteBase)fDeal;
DateGenerationRequest dateGenerationRequest = new DateGenerationRequest
{
RequiresPayDates = true,
RequiresResetDates = true,
RequiresYearFractions = true,
};
DateGenerationParams dateGenerationParams = new DateGenerationParams
{
EffectiveDate = deal.Effective_Date,
MaturityDate = deal.Maturity_Date,
CouponPeriod = deal.Coupon_Interval,
AccrualCalendar = deal.GetHolidayCalendar(),
AccrualDayCount = deal.Accrual_Day_Count,
};
DateGenerationResults dateGenerationResults = CashflowGeneration.GenerateCashflowDateAndValueLists(dateGenerationRequest, dateGenerationParams);
PayDates = dateGenerationResults.PayDates;
Accruals = dateGenerationResults.AccrualYearFractions;
ResetDates = dateGenerationResults.ResetDates;
// Add to valuation time grid
bool cashRequired = ResultsRequired.CashRequired();
fT.AddPayDate(deal.Effective_Date, cashRequired);
fT.AddPayDates(PayDates, cashRequired);
}
/// <summary>
/// Vector valuation function.
/// </summary>
public override void Value(ValuationResults valuationResults, PriceFactorList factors, BaseTimeGrid baseTimes)
{
PreValue(factors);
TimeGridIterator tgi = new TimeGridIterator(fT);
PVProfiles result = valuationResults.Profile;
CashAccumulators accumulator = valuationResults.Cash;
DealCreditLinkedNoteBase deal = (DealCreditLinkedNoteBase)fDeal;
ISurvivalProb SP = GetSurvivalProbability(factors);
RecoveryRate RR = GetRecoveryRate(factors);
CreditRating CR = GetCreditRating(factors);
double tEffective = CalcUtils.DaysToYears(deal.Effective_Date - factors.BaseDate);
double scale = (deal.Buy_Sell == BuySell.Buy) ? +deal.Notional_Amount : -deal.Notional_Amount;
double purchasePrice = Percentage.PercentagePoint * deal.Price;
double couponRate = (deal.Coupon_Type == InterestRateType.Fixed) ? Percentage.PercentagePoint * deal.Coupon_Rate : 0.0;
double couponSpread = (deal.Coupon_Type == InterestRateType.Fixed) ? 0.0 : BasisPoint.BasisPointValue * deal.Coupon_Spread;
double indexTenor = (deal.Index_Tenor > 0.0) ? deal.Index_Tenor : deal.Coupon_Interval;
using (var cache = Vector.Cache(factors.NumScenarios))
{
bool[] hasDefaulted = (Respect_Default == YesNo.Yes) ? new bool[factors.NumScenarios] : null;
Vector defaultTime = (Respect_Default == YesNo.Yes) ? cache.Get() : null;
Vector historicalRecovery = (Respect_Default == YesNo.Yes) ? cache.GetClear() : null;
if (hasDefaulted != null && CR != null)
{
DefaultTime(defaultTime, CR);
}
Vector npv = cache.Get();
Vector cash = cache.Get();
Vector pStart = cache.Get();
Vector pEnd = cache.Get();
Vector amount = cache.Get();
Vector recovery = cache.Get();
Vector dfLast = cache.Get();
Vector df = cache.Get();
cash.Clear();
var defaultedBeforeTheBaseDate = Respect_Default == YesNo.Yes &&
CreditRating.DefaultedBeforeBaseDate(CR, factors.BaseDate);
while (tgi.Next())
{
if (defaultedBeforeTheBaseDate)
{
npv.Clear();
result.AppendVector(tgi.Date, npv);
break;
}
if (!deal.Principal_Guaranteed && Respect_Default == YesNo.Yes)
{
RealizedRecoveryRate(recovery, RR, tgi.T);
}
// Assume defaults are rare and start by valuing under all scenarios without realized defaults
// Value of principal repayment
SurvivalProbability(pEnd, factors, SP, tgi.T, fT.fLast);
fDiscountRate.GetValue(dfLast, tgi.T, fT.fLast);
if (deal.Principal_Guaranteed)
{
npv.Assign(dfLast);
}
else
{
npv.Assign(dfLast * pEnd);
}
if (accumulator != null && tgi.T == fT.fLast)
{
cash.Assign(npv);
}
// Value of coupons
for (int i = PayDates.Count - 1; i >= 0 && tgi.Date <= PayDates[i]; --i)
{
double tPay = CalcUtils.DaysToYears(PayDates[i] - factors.BaseDate);
double tReset = CalcUtils.DaysToYears(ResetDates[i] - factors.BaseDate);
double tPrevious = Math.Max(tgi.T, tReset);
SurvivalProbability(pStart, factors, SP, tgi.T, tPrevious);
if (deal.Coupon_Type == InterestRateType.Floating)
{
// Forecast a coupon, add the spread
InterestRateUtils.LiborRate(amount, fForecastRate, tgi.T, tReset, tReset, tReset + indexTenor, deal.Index_Day_Count);
amount.Add(couponSpread);
amount.MultiplyBy(Accruals[i]);
}
else
{
// Fixed coupon
amount.Assign(couponRate * Accruals[i]);
}
// The value of the coupon if no default
npv.Add(amount * fDiscountRate.Get(tgi.T, tPay) * pEnd);
if (accumulator != null && tgi.T == tPay)
{
cash.Assign(amount);
}
// The recovery value on default - assume guaranteed principal paid at end, recovery paid immediately
if (!deal.Principal_Guaranteed)
{
npv.Add(fDiscountRate.Get(tgi.T, 0.5 * (tPay + tPrevious)) * (pStart - pEnd) * PricingRecoveryRate(SP));
}
pEnd.DestructiveAssign(pStart);
}
// Now check for realized default scenario by scenario, overwriting NPV and cash as appropriate
if (Respect_Default == YesNo.Yes && defaultTime != null)
{
if (tgi.T < tEffective)
{
fDiscountRate.GetValue(df, tgi.T, tEffective);
}
for (int i = 0; i < npv.Count; ++i)
{
if (defaultTime[i] > tgi.T)
{
continue;
}
if (deal.Principal_Guaranteed)
{
npv[i] = dfLast[i]; // full principal paid at maturity
}
else
{
if (!hasDefaulted[i])
{
historicalRecovery[i] = recovery[i]; // record the historical recovery rate
}
if (tgi.T < tEffective)
{
npv[i] = df[i] * historicalRecovery[i]; // The discounted recovery value of the principal will be paid out on the effective date
}
else if (tgi.T == tEffective || !hasDefaulted[i])
{
npv[i] = historicalRecovery[i]; // The full recovery amount is paid out
}
else
{
npv[i] = 0.0; // default is in the past but we are after effective date; settlement has already occurred.
}
}
hasDefaulted[i] = true;
}
}
// Value of purchase price
if (tgi.T < tEffective)
{
npv.Add(-purchasePrice * fDiscountRate.Get(tgi.T, tEffective));
}
else if (tgi.T == tEffective)
{
npv.Add(-purchasePrice);
if (accumulator != null)
{
cash.Add(-purchasePrice);
}
}
result.AppendVector(tgi.Date, scale * npv * fFxRate.Get(tgi.T));
if (accumulator != null)
{
accumulator.Accumulate(fFxRate, tgi.Date, scale * cash);
}
}
// After maturity
result.Complete(fT);
}
}
