/**
* Copyright (C) 2011 - present by OpenGamma Inc. and the OpenGamma group of companies
*
* Please see distribution for license.
*/
package com.opengamma.analytics.financial.forex.provider;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.opengamma.analytics.financial.forex.derivative.Forex;
import com.opengamma.analytics.financial.interestrate.payments.provider.PaymentFixedDiscountingMethod;
import com.opengamma.analytics.financial.provider.description.interestrate.MulticurveProviderInterface;
import com.opengamma.analytics.financial.provider.sensitivity.multicurve.MulticurveSensitivity;
import com.opengamma.analytics.financial.provider.sensitivity.multicurve.MultipleCurrencyMulticurveSensitivity;
import com.opengamma.util.ArgumentChecker;
import com.opengamma.util.money.Currency;
import com.opengamma.util.money.MultipleCurrencyAmount;
import com.opengamma.util.tuple.DoublesPair;
/**
* Pricing method for Forex transactions (spot or forward) by discounting each payment.
*/
public final class ForexDiscountingMethod {
/**
* The method unique instance.
*/
private static final ForexDiscountingMethod INSTANCE = new ForexDiscountingMethod();
/**
* Return the unique instance of the class.
* @return The instance.
*/
public static ForexDiscountingMethod getInstance() {
return INSTANCE;
}
/**
* Private constructor.
*/
private ForexDiscountingMethod() {
}
/**
* Fixed payments method.
*/
private static final PaymentFixedDiscountingMethod METHOD_PAY = PaymentFixedDiscountingMethod.getInstance();
/**
* Computes the present value by discounting each payment in its own currency.
* @param fx The Forex derivative.
* @param multicurves The multi-curves provider.
* @return The multi-currency present value.
*/
public MultipleCurrencyAmount presentValue(final Forex fx, final MulticurveProviderInterface multicurves) {
final MultipleCurrencyAmount pv1 = METHOD_PAY.presentValue(fx.getPaymentCurrency1(), multicurves);
final MultipleCurrencyAmount pv2 = METHOD_PAY.presentValue(fx.getPaymentCurrency2(), multicurves);
return pv1.plus(pv2);
}
/**
* Computes the currency exposure by discounting each payment in its own currency.
* @param fx The Forex derivative.
* @param multicurves The multi-curves provider.
* @return The multi-currency present value.
*/
public MultipleCurrencyAmount currencyExposure(final Forex fx, final MulticurveProviderInterface multicurves) {
return presentValue(fx, multicurves);
}
/**
* The par spread is the spread that should be added to the forex forward points to have a zero value.
* @param fx The forex swap.
* @param multicurves The multi-curves provider.
* @return The spread.
*/
public double parSpread(final Forex fx, final MulticurveProviderInterface multicurves) {
ArgumentChecker.notNull(fx, "Forex");
ArgumentChecker.notNull(multicurves, "Multi-curves provider");
final Currency ccy2 = fx.getCurrency2();
final double pv2 = multicurves.getFxRates().convert(presentValue(fx, multicurves), ccy2).getAmount();
final double dfEnd = multicurves.getDiscountFactor(fx.getCurrency2(), fx.getPaymentTime());
final double notional1 = fx.getPaymentCurrency1().getAmount();
return pv2 / (notional1 * dfEnd);
}
/**
* Computes the forward exchange rate associated to the Forex instrument (1 Cyy1 = fwd Cyy2).
* @param fx The Forex derivative.
* @param multicurves The multi-curve provider.
* @return The forward rate.
*/
public double forwardForexRate(final Forex fx, final MulticurveProviderInterface multicurves) {
final double dfDomestic = multicurves.getDiscountFactor(fx.getCurrency2(), fx.getPaymentTime());
final double dfForeign = multicurves.getDiscountFactor(fx.getCurrency1(), fx.getPaymentTime());
final double spot = multicurves.getFxRate(fx.getCurrency1(), fx.getCurrency2());
return spot * dfForeign / dfDomestic;
}
/**
* Compute the present value sensitivity to rates of a forex transaction.
* @param fx The Forex transaction.
* @param multicurves The multi-curve provider.
* @return The sensitivity.
*/
public MultipleCurrencyMulticurveSensitivity presentValueCurveSensitivity(final Forex fx, final MulticurveProviderInterface multicurves) {
final MultipleCurrencyMulticurveSensitivity pvcs1 = METHOD_PAY.presentValueCurveSensitivity(fx.getPaymentCurrency1(), multicurves);
final MultipleCurrencyMulticurveSensitivity pvcs2 = METHOD_PAY.presentValueCurveSensitivity(fx.getPaymentCurrency2(), multicurves);
return pvcs1.plus(pvcs2);
}
/**
* Computes the par spread curve sensitivity.
* @param fx The forex swap.
* @param multicurves The multi-curves provider.
* @return The par spread sensitivity.
*/
public MulticurveSensitivity parSpreadCurveSensitivity(final Forex fx, final MulticurveProviderInterface multicurves) {
ArgumentChecker.notNull(fx, "Forex");
ArgumentChecker.notNull(multicurves, "Multi-curves provider");
final Currency ccy2 = fx.getCurrency2();
final double payTime = fx.getPaymentTime();
final double pv2 = multicurves.getFxRates().convert(presentValue(fx, multicurves), ccy2).getAmount();
final double dfEnd = multicurves.getDiscountFactor(fx.getCurrency2(), fx.getPaymentTime());
final double notional1 = fx.getPaymentCurrency1().getAmount();
// Backward sweep
final double spreadBar = 1.0;
final double dfEndBar = -pv2 / (notional1 * dfEnd * dfEnd) * spreadBar;
final double pv2Bar = spreadBar / (notional1 * dfEnd);
final MultipleCurrencyMulticurveSensitivity pv2DrMC = presentValueCurveSensitivity(fx, multicurves);
final MulticurveSensitivity pv2Dr = pv2DrMC.converted(ccy2, multicurves.getFxRates()).getSensitivity(ccy2);
final List<DoublesPair> list = new ArrayList<>();
list.add(DoublesPair.of(payTime, -payTime * dfEnd * dfEndBar));
final Map<String, List<DoublesPair>> result = new HashMap<>();
result.put(multicurves.getName(ccy2), list);
final MulticurveSensitivity dfEndDr = MulticurveSensitivity.ofYieldDiscounting(result);
return pv2Dr.multipliedBy(pv2Bar).plus(dfEndDr);
}
}