//-------------------------------------------------------------------------
// print for debugging
protected internal virtual void print(IborCapletFloorletVolatilityCalibrationResult res, DoubleArray strikes, double maxTime)
{
Console.WriteLine("Print in CapletStrippingSetup \n");
Console.WriteLine("Chi-square: " + res.ChiSquare);
IborCapletFloorletVolatilities vols = res.Volatilities;
const int nSamples = 51;
const int nStrikeSamples = 51;
Console.Write("\n");
for (int i = 0; i < nStrikeSamples; i++)
{
Console.Write("\t" + (strikes.get(0) + (strikes.get(strikes.size() - 1) - strikes.get(0)) * i) / (nStrikeSamples - 1));
}
Console.Write("\n");
for (int index = 0; index < nSamples; index++)
{
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final double t = 0.25 + index * maxTime / (nSamples - 1);
double t = 0.25 + index * maxTime / (nSamples - 1);
double forward = FWD_CURVE.yValue(t);
Console.Write(t);
for (int i = 0; i < nStrikeSamples; i++)
{
double strike = (strikes.get(0) + (strikes.get(strikes.size() - 1) - strikes.get(0)) * i) / (nStrikeSamples - 1);
Console.Write("\t" + vols.volatility(t, strike, forward));
}
Console.Write("\n");
}
}
//-------------------------------------------------------------------------
/// <summary>
/// Calculates the present value of the Ibor caplet/floorlet period.
/// <para>
/// The result is expressed using the currency of the period.
///
/// </para>
/// </summary>
/// <param name="period"> the Ibor caplet/floorlet period </param>
/// <param name="ratesProvider"> the rates provider </param>
/// <param name="volatilities"> the volatilities </param>
/// <returns> the present value </returns>
public virtual CurrencyAmount presentValue(IborCapletFloorletPeriod period, RatesProvider ratesProvider, IborCapletFloorletVolatilities volatilities)
{
validate(volatilities);
Currency currency = period.Currency;
if (ratesProvider.ValuationDate.isAfter(period.PaymentDate))
{
return(CurrencyAmount.of(currency, 0d));
}
double expiry = volatilities.relativeTime(period.FixingDateTime);
double df = ratesProvider.discountFactor(currency, period.PaymentDate);
PutCall putCall = period.PutCall;
double strike = period.Strike;
double indexRate = ratesProvider.iborIndexRates(period.Index).rate(period.IborRate.Observation);
if (expiry < 0d)
{ // Option has expired already
double sign = putCall.Call ? 1d : -1d;
double payoff = Math.Max(sign * (indexRate - strike), 0d);
return(CurrencyAmount.of(currency, df * payoff * period.YearFraction * period.Notional));
}
double volatility = volatilities.volatility(expiry, strike, indexRate);
double price = df * period.YearFraction * volatilities.price(expiry, putCall, strike, indexRate, volatility);
return(CurrencyAmount.of(currency, price * period.Notional));
}
//-------------------------------------------------------------------------
/// <summary>
/// Calculates the present value rates sensitivity of the Ibor caplet/floorlet.
/// <para>
/// The present value rates sensitivity of the caplet/floorlet is the sensitivity
/// of the present value to the underlying curves.
///
/// </para>
/// </summary>
/// <param name="period"> the Ibor caplet/floorlet period </param>
/// <param name="ratesProvider"> the rates provider </param>
/// <param name="volatilities"> the volatilities </param>
/// <returns> the present value curve sensitivity </returns>
public virtual PointSensitivityBuilder presentValueSensitivityRates(IborCapletFloorletPeriod period, RatesProvider ratesProvider, IborCapletFloorletVolatilities volatilities)
{
validate(volatilities);
Currency currency = period.Currency;
if (ratesProvider.ValuationDate.isAfter(period.PaymentDate))
{
return(PointSensitivityBuilder.none());
}
double expiry = volatilities.relativeTime(period.FixingDateTime);
PutCall putCall = period.PutCall;
double strike = period.Strike;
double indexRate = ratesProvider.iborIndexRates(period.Index).rate(period.IborRate.Observation);
PointSensitivityBuilder dfSensi = ratesProvider.discountFactors(currency).zeroRatePointSensitivity(period.PaymentDate);
if (expiry < 0d)
{ // Option has expired already
double sign = putCall.Call ? 1d : -1d;
double payoff = Math.Max(sign * (indexRate - strike), 0d);
return(dfSensi.multipliedBy(payoff * period.YearFraction * period.Notional));
}
PointSensitivityBuilder indexRateSensiSensi = ratesProvider.iborIndexRates(period.Index).ratePointSensitivity(period.IborRate.Observation);
double volatility = volatilities.volatility(expiry, strike, indexRate);
double df = ratesProvider.discountFactor(currency, period.PaymentDate);
double factor = period.Notional * period.YearFraction;
double fwdPv = factor * volatilities.price(expiry, putCall, strike, indexRate, volatility);
double fwdDelta = factor * volatilities.priceDelta(expiry, putCall, strike, indexRate, volatility);
return(dfSensi.multipliedBy(fwdPv).combinedWith(indexRateSensiSensi.multipliedBy(fwdDelta * df)));
}
//-------------------------------------------------------------------------
/// <summary>
/// Computes the implied volatility of the Ibor caplet/floorlet.
/// </summary>
/// <param name="period"> the Ibor caplet/floorlet period </param>
/// <param name="ratesProvider"> the rates provider </param>
/// <param name="volatilities"> the volatilities </param>
/// <returns> the implied volatility </returns>
public virtual double impliedVolatility(IborCapletFloorletPeriod period, RatesProvider ratesProvider, IborCapletFloorletVolatilities volatilities)
{
validate(volatilities);
double expiry = volatilities.relativeTime(period.FixingDateTime);
ArgChecker.isTrue(expiry >= 0d, "Option must be before expiry to compute an implied volatility");
double forward = ratesProvider.iborIndexRates(period.Index).rate(period.IborRate.Observation);
double strike = period.Strike;
return(volatilities.volatility(expiry, strike, forward));
}
//-------------------------------------------------------------------------
/// <summary>
/// Calculates the present value volatility sensitivity of the Ibor caplet/floorlet.
/// <para>
/// The present value volatility sensitivity of the caplet/floorlet is the sensitivity
/// of the present value to the implied volatility.
/// </para>
/// <para>
/// The sensitivity to the implied volatility is also called vega.
///
/// </para>
/// </summary>
/// <param name="period"> the Ibor caplet/floorlet period </param>
/// <param name="ratesProvider"> the rates provider </param>
/// <param name="volatilities"> the volatilities </param>
/// <returns> the point sensitivity to the volatility </returns>
public virtual PointSensitivityBuilder presentValueSensitivityModelParamsVolatility(IborCapletFloorletPeriod period, RatesProvider ratesProvider, IborCapletFloorletVolatilities volatilities)
{
validate(volatilities);
double expiry = volatilities.relativeTime(period.FixingDateTime);
double strike = period.Strike;
Currency currency = period.Currency;
if (expiry <= 0d)
{ // Option has expired already or at expiry
return(PointSensitivityBuilder.none());
}
double forward = ratesProvider.iborIndexRates(period.Index).rate(period.IborRate.Observation);
double volatility = volatilities.volatility(expiry, strike, forward);
PutCall putCall = period.PutCall;
double df = ratesProvider.discountFactor(currency, period.PaymentDate);
double vega = df * period.YearFraction * volatilities.priceVega(expiry, putCall, strike, forward, volatility);
return(IborCapletFloorletSensitivity.of(volatilities.Name, expiry, strike, forward, currency, vega * period.Notional));
}
//-------------------------------------------------------------------------
/// <summary>
/// Calculates the present value theta of the Ibor caplet/floorlet period.
/// <para>
/// The present value theta is given by the minus of the present value sensitivity to the {@code timeToExpiry}
/// parameter of the model.
///
/// </para>
/// </summary>
/// <param name="period"> the Ibor caplet/floorlet period </param>
/// <param name="ratesProvider"> the rates provider </param>
/// <param name="volatilities"> the volatilities </param>
/// <returns> the present value theta </returns>
public virtual CurrencyAmount presentValueTheta(IborCapletFloorletPeriod period, RatesProvider ratesProvider, IborCapletFloorletVolatilities volatilities)
{
validate(volatilities);
double expiry = volatilities.relativeTime(period.FixingDateTime);
Currency currency = period.Currency;
if (expiry < 0d)
{ // Option has expired already
return(CurrencyAmount.of(currency, 0d));
}
double forward = ratesProvider.iborIndexRates(period.Index).rate(period.IborRate.Observation);
double strike = period.Strike;
double volatility = volatilities.volatility(expiry, strike, forward);
PutCall putCall = period.PutCall;
double df = ratesProvider.discountFactor(currency, period.PaymentDate);
double priceTheta = df * period.YearFraction * volatilities.priceTheta(expiry, putCall, strike, forward, volatility);
return(CurrencyAmount.of(currency, priceTheta * period.Notional));
}
