public override void calculate()
{
AmericanExercise ex = arguments_.exercise as AmericanExercise;
Utils.QL_REQUIRE(ex != null, () => "non-American exercise given");
Utils.QL_REQUIRE(ex.payoffAtExpiry(), () => "payoff must be at expiry");
Utils.QL_REQUIRE(ex.dates()[0] <= process_.blackVolatility().link.referenceDate(), () =>
"American option with window exercise not handled yet");
StrikedTypePayoff payoff = arguments_.payoff as StrikedTypePayoff;
Utils.QL_REQUIRE(payoff != null, () => "non-striked payoff given");
double spot = process_.stateVariable().link.value();
Utils.QL_REQUIRE(spot > 0.0, () => "negative or null underlying given");
double variance = process_.blackVolatility().link.blackVariance(ex.lastDate(), payoff.strike());
double?barrier = arguments_.barrier;
Utils.QL_REQUIRE(barrier > 0.0, () => "positive barrier value required");
Barrier.Type barrierType = arguments_.barrierType;
// KO degenerate cases
if ((barrierType == Barrier.Type.DownOut && spot <= barrier) ||
(barrierType == Barrier.Type.UpOut && spot >= barrier))
{
// knocked out, no value
results_.value = 0;
results_.delta = 0;
results_.gamma = 0;
results_.vega = 0;
results_.theta = 0;
results_.rho = 0;
results_.dividendRho = 0;
return;
}
// KI degenerate cases
if ((barrierType == Barrier.Type.DownIn && spot <= barrier) ||
(barrierType == Barrier.Type.UpIn && spot >= barrier))
{
// knocked in - is a digital european
Exercise exercise = new EuropeanExercise(arguments_.exercise.lastDate());
IPricingEngine engine = new AnalyticEuropeanEngine(process_);
VanillaOption opt = new VanillaOption(payoff, exercise);
opt.setPricingEngine(engine);
results_.value = opt.NPV();
results_.delta = opt.delta();
results_.gamma = opt.gamma();
results_.vega = opt.vega();
results_.theta = opt.theta();
results_.rho = opt.rho();
results_.dividendRho = opt.dividendRho();
return;
}
double riskFreeDiscount = process_.riskFreeRate().link.discount(ex.lastDate());
AnalyticBinaryBarrierEngine_helper helper = new AnalyticBinaryBarrierEngine_helper(
process_, payoff, ex, arguments_);
results_.value = helper.payoffAtExpiry(spot, variance, riskFreeDiscount);
}
