protected Set<ComputedValue> getResult(final InstrumentDerivative fxDigital, final ForexOptionDataBundle<?> data, final ComputationTarget target,
final Set<ValueRequirement> desiredValues, final FunctionInputs inputs, final ValueSpecification spec, final FunctionExecutionContext executionContext) {
final String spreadName = Iterables.getOnlyElement(desiredValues).getConstraint(CalculationPropertyNamesAndValues.PROPERTY_CALL_SPREAD_VALUE);
final double spread = Double.parseDouble(spreadName);
final PresentValueBlackVolatilitySensitivityCallSpreadBlackForexCalculator calculator = new PresentValueBlackVolatilitySensitivityCallSpreadBlackForexCalculator(spread);
final PresentValueForexBlackVolatilitySensitivity result = fxDigital.accept(calculator, data);
final CurrencyAmount vegaValue = result.toSingleValue();
return Collections.singleton(new ComputedValue(spec, vegaValue.getAmount()));
}