Пример #1
0
        public void TestBlockGenerationSobolFlipShifted()
        {
            var engine           = new PathEngine(64);
            var directionNumbers = new Random.Sobol.SobolDirectionNumbers("SobolDirectionNumbers.txt");

            engine.AddPathProcess(new Random.Sobol.SobolFlipShiftedPathGenerator(true, directionNumbers));
            engine.AddPathProcess(new FakeAssetProcess("TestUnderlying", numberOfDimensions: 2, timesteps: 10));
            engine.SetupFeatures();
            engine.RunProcess();
        }
Пример #2
0
        public AssetFxMCModel(DateTime originDate, Portfolio portfolio, IAssetFxModel model, McSettings settings, ICurrencyProvider currencyProvider, IFutureSettingsProvider futureSettingsProvider, ICalendarProvider calendarProvider)
        {
            if (settings.CompactMemoryMode && settings.AveragePathCorrection)
            {
                throw new Exception("Can't use both CompactMemoryMode and PathCorrection");
            }

            _currencyProvider       = currencyProvider;
            _futureSettingsProvider = futureSettingsProvider;
            _calendarProvider       = calendarProvider;
            Engine = new PathEngine(settings.NumberOfPaths)
            {
                Parallelize       = settings.Parallelize,
                CompactMemoryMode = settings.CompactMemoryMode
            };
            OriginDate = originDate;
            Portfolio  = portfolio;
            Model      = model;
            Settings   = settings;
            switch (settings.Generator)
            {
            case RandomGeneratorType.MersenneTwister:
                Engine.AddPathProcess(new Random.MersenneTwister.MersenneTwister64()
                {
                    UseNormalInverse = true,
                    UseAnthithetic   = false
                });
                break;

            case RandomGeneratorType.Sobol:
                var directionNumers = new Random.Sobol.SobolDirectionNumbers(GetSobolFilename());
                Engine.AddPathProcess(new Random.Sobol.SobolPathGenerator(directionNumers, 1000)
                {
                    UseNormalInverse = true
                });
                break;

            case RandomGeneratorType.Constant:
                Engine.AddPathProcess(new Random.Constant.Constant()
                {
                    UseNormalInverse = true,
                });
                break;

            case RandomGeneratorType.FlipFlop:
                Engine.AddPathProcess(new Random.Constant.FlipFlop(settings.CreditSettings.ConfidenceInterval, true));
                break;
            }
            Engine.IncrementDepth();

            if (model.CorrelationMatrix != null)
            {
                if (settings.LocalCorrelation)
                {
                    Engine.AddPathProcess(new CholeskyWithTime(model.CorrelationMatrix, model));
                }
                else
                {
                    Engine.AddPathProcess(new Cholesky(model.CorrelationMatrix));
                }
                Engine.IncrementDepth();
            }

            var lastDate         = portfolio.LastSensitivityDate;
            var assetIds         = portfolio.AssetIds();
            var assetInstruments = portfolio.Instruments
                                   .Where(x => x is IAssetInstrument)
                                   .Select(x => x as IAssetInstrument);
            var fixingsNeeded = new Dictionary <string, List <DateTime> >();

            foreach (var ins in assetInstruments)
            {
                var fixingsForIns = ins.PastFixingDates(originDate);
                if (fixingsForIns.Any())
                {
                    foreach (var kv in fixingsForIns)
                    {
                        if (!fixingsNeeded.ContainsKey(kv.Key))
                        {
                            fixingsNeeded.Add(kv.Key, new List <DateTime>());
                        }
                        fixingsNeeded[kv.Key] = fixingsNeeded[kv.Key].Concat(kv.Value).Distinct().ToList();
                    }
                }
            }

            //asset processes
            var fxAssetsToAdd = new List <string>();
            var corrections   = new Dictionary <string, SimpleAveragePathCorrector>();

            foreach (var assetId in assetIds)
            {
                if (assetId.Length == 7 && assetId[3] == '/')
                {
                    fxAssetsToAdd.Add(assetId);
                    continue;
                }

                if (!(model.GetVolSurface(assetId) is IATMVolSurface surface))
                {
                    throw new Exception($"Vol surface for asset {assetId} could not be cast to IATMVolSurface");
                }
                var fixingDict = fixingsNeeded.ContainsKey(assetId) ? model.GetFixingDictionary(assetId) : null;
                var fixings    = fixingDict != null ?
                                 fixingsNeeded[assetId].ToDictionary(x => x, x => fixingDict.GetFixing(x))
                    : new Dictionary <DateTime, double>();
                var futuresSim = settings.ExpensiveFuturesSimulation &&
                                 (model.GetPriceCurve(assetId).CurveType == PriceCurveType.ICE || model.GetPriceCurve(assetId).CurveType == PriceCurveType.NYMEX);
                if (futuresSim)
                {
                    var fwdCurve = new Func <DateTime, double>(t =>
                    {
                        return(model.GetPriceCurve(assetId).GetPriceForDate(t));
                    });
                    var asset = new BlackFuturesCurve
                                (
                        startDate: originDate,
                        expiryDate: lastDate,
                        volSurface: surface,
                        forwardCurve: fwdCurve,
                        nTimeSteps: settings.NumberOfTimesteps,
                        name: Settings.FuturesMappingTable[assetId],
                        pastFixings: fixings,
                        futureSettingsProvider: _futureSettingsProvider
                                );
                    Engine.AddPathProcess(asset);
                }
                else
                {
                    var fwdCurve = new Func <double, double>(t =>
                    {
                        var c = model.GetPriceCurve(assetId);
                        var d = originDate.AddYearFraction(t, DayCountBasis.ACT365F);
                        if (c is PriceCurve pc)
                        {
                            d = d.AddPeriod(RollType.F, pc.SpotCalendar, pc.SpotLag);
                        }
                        else if (c is ContangoPriceCurve cc)
                        {
                            d = d.AddPeriod(RollType.F, cc.SpotCalendar, cc.SpotLag);
                        }
                        return(c.GetPriceForDate(d));
                    });

                    IATMVolSurface adjSurface  = null;
                    var            correlation = 0.0;

                    if (settings.ReportingCurrency != model.GetPriceCurve(assetId).Currency)
                    {
                        var fxAdjPair    = settings.ReportingCurrency + "/" + model.GetPriceCurve(assetId).Currency;
                        var fxAdjPairInv = model.GetPriceCurve(assetId).Currency + "/" + settings.ReportingCurrency;
                        if (!(model.FundingModel.GetVolSurface(fxAdjPair) is IATMVolSurface adjSurface2))
                        {
                            throw new Exception($"Vol surface for fx pair {fxAdjPair} could not be cast to IATMVolSurface");
                        }
                        adjSurface = adjSurface2;
                        if (model.CorrelationMatrix != null)
                        {
                            if (model.CorrelationMatrix.TryGetCorrelation(fxAdjPair, assetId, out var correl))
                            {
                                correlation = correl;
                            }
                            else if (model.CorrelationMatrix.TryGetCorrelation(fxAdjPairInv, assetId, out var correl2))
                            {
                                correlation = -correl2;
                            }
                        }
                    }

                    if (settings.McModelType == McModelType.LocalVol)
                    {
                        var asset = new LVSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: assetId,
                            pastFixings: fixings,
                            fxAdjustSurface: adjSurface,
                            fxAssetCorrelation: correlation
                                    );
                        Engine.AddPathProcess(asset);
                    }
                    else if (settings.McModelType == McModelType.TurboSkew)
                    {
                        var asset = new TurboSkewSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: assetId,
                            pastFixings: fixings,
                            fxAdjustSurface: adjSurface,
                            fxAssetCorrelation: correlation
                                    );
                        Engine.AddPathProcess(asset);
                    }
                    else
                    {
                        var asset = new BlackSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: assetId,
                            pastFixings: fixings,
                            fxAdjustSurface: adjSurface,
                            fxAssetCorrelation: correlation
                                    );
                        Engine.AddPathProcess(asset);
                    }
                    if (settings.AveragePathCorrection)
                    {
                        corrections.Add(assetId, new SimpleAveragePathCorrector(new SimpleAveragePathCalculator(assetId)
                        {
                            CompactMode = settings.CompactMemoryMode
                        }, surface, fwdCurve, assetId, fixings, adjSurface, correlation));
                    }
                }
            }

            //fx pairs
            var pairsAdded = new List <string>();
            var fxPairs    = portfolio.FxPairs(model).Concat(fxAssetsToAdd);
            var payoutCcys = portfolio.Instruments.Select(i => i.Currency);

            if (payoutCcys.Any(p => p != settings.ReportingCurrency))
            {
                var ccysToAdd  = payoutCcys.Where(p => p != settings.ReportingCurrency).Distinct();
                var pairsToAdd = ccysToAdd.Select(c => $"{c.Ccy}/{settings.ReportingCurrency}");
                fxPairs = fxPairs.Concat(pairsToAdd).Distinct();
            }
            foreach (var fxPair in fxPairs)
            {
                var fxPairName = fxPair;
                var pair       = fxPairName.FxPairFromString(_currencyProvider, _calendarProvider);

                if (pairsAdded.Contains(pair.ToString()))
                {
                    continue;
                }

                if (!(model.FundingModel.VolSurfaces[fxPairName] is IATMVolSurface surface))
                {
                    throw new Exception($"Vol surface for fx pair {fxPairName} could not be cast to IATMVolSurface");
                }

                var fwdCurve = new Func <double, double>(t =>
                {
                    var date     = originDate.AddYearFraction(t, DayCountBasis.ACT365F);
                    var spotDate = pair.SpotDate(date);
                    return(model.FundingModel.GetFxRate(spotDate, fxPairName));
                });

                pairsAdded.Add(pair.ToString());

                if (settings.McModelType == McModelType.LocalVol)
                {
                    var asset = new LVSingleAsset
                                (
                        startDate: originDate,
                        expiryDate: lastDate,
                        volSurface: surface,
                        forwardCurve: fwdCurve,
                        nTimeSteps: settings.NumberOfTimesteps,
                        name: fxPairName
                                );
                    Engine.AddPathProcess(asset);

                    if (settings.AveragePathCorrection)
                    {
                        corrections.Add(fxPairName, new SimpleAveragePathCorrector(new SimpleAveragePathCalculator(fxPairName)
                        {
                            CompactMode = settings.CompactMemoryMode
                        }, surface, fwdCurve, fxPairName));
                    }
                }
                else if (settings.McModelType == McModelType.TurboSkew)
                {
                    if (fxPairName.Substring(fxPairName.Length - 3, 3) != settings.ReportingCurrency)
                    {//needs to be drift-adjusted
                        var fxAdjPair = settings.ReportingCurrency + "/" + fxPairName.Substring(fxPairName.Length - 3, 3);
                        if (!(model.FundingModel.VolSurfaces[fxAdjPair] is IATMVolSurface adjSurface))
                        {
                            throw new Exception($"Vol surface for fx pair {fxAdjPair} could not be cast to IATMVolSurface");
                        }
                        var correlation = fxPair == fxAdjPair ? -1.0 : 0.0;
                        if (correlation != -1.0 && model.CorrelationMatrix != null)
                        {
                            if (model.CorrelationMatrix.TryGetCorrelation(fxAdjPair, fxPair, out var correl))
                            {
                                correlation = correl;
                            }
                        }

                        var asset = new TurboSkewSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: fxPairName,
                            fxAdjustSurface: adjSurface,
                            fxAssetCorrelation: correlation
                                    );
                        Engine.AddPathProcess(asset);

                        if (settings.AveragePathCorrection)
                        {
                            corrections.Add(fxPairName, new SimpleAveragePathCorrector(new SimpleAveragePathCalculator(fxPairName)
                            {
                                CompactMode = settings.CompactMemoryMode
                            }, surface, fwdCurve, fxPairName, null, adjSurface, correlation));
                        }
                    }
                    else
                    {
                        var asset = new TurboSkewSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: fxPairName
                                    );
                        Engine.AddPathProcess(asset);

                        if (settings.AveragePathCorrection)
                        {
                            corrections.Add(fxPairName, new SimpleAveragePathCorrector(new SimpleAveragePathCalculator(fxPairName)
                            {
                                CompactMode = settings.CompactMemoryMode
                            }, surface, fwdCurve, fxPairName));
                        }
                    }
                }
                else
                {
                    if (fxPairName.Substring(fxPairName.Length - 3, 3) != settings.ReportingCurrency)
                    {//needs to be drift-adjusted
                        var fxAdjPair = settings.ReportingCurrency + "/" + fxPairName.Substring(fxPairName.Length - 3, 3);
                        if (!(model.FundingModel.VolSurfaces[fxAdjPair] is IATMVolSurface adjSurface))
                        {
                            throw new Exception($"Vol surface for fx pair {fxAdjPair} could not be cast to IATMVolSurface");
                        }
                        var correlation = fxPair == fxAdjPair ? -1.0 : 0.0;
                        if (correlation != -1.0 && model.CorrelationMatrix != null)
                        {
                            if (model.CorrelationMatrix.TryGetCorrelation(fxAdjPair, fxPair, out var correl))
                            {
                                correlation = correl;
                            }
                        }

                        var asset = new BlackSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: fxPairName,
                            fxAdjustSurface: adjSurface,
                            fxAssetCorrelation: correlation
                                    );
                        Engine.AddPathProcess(asset);

                        if (settings.AveragePathCorrection)
                        {
                            corrections.Add(fxPairName, new SimpleAveragePathCorrector(new SimpleAveragePathCalculator(fxPairName)
                            {
                                CompactMode = settings.CompactMemoryMode
                            }, surface, fwdCurve, fxPairName, null, adjSurface, correlation));
                        }
                    }
                    else
                    {
                        var asset = new BlackSingleAsset
                                    (
                            startDate: originDate,
                            expiryDate: lastDate,
                            volSurface: surface,
                            forwardCurve: fwdCurve,
                            nTimeSteps: settings.NumberOfTimesteps,
                            name: fxPairName
                                    );
                        Engine.AddPathProcess(asset);

                        if (settings.AveragePathCorrection)
                        {
                            corrections.Add(fxPairName, new SimpleAveragePathCorrector(new SimpleAveragePathCalculator(fxPairName)
                            {
                                CompactMode = settings.CompactMemoryMode
                            }, surface, fwdCurve, fxPairName));
                        }
                    }
                }
            }
            //apply path correctin
            if (settings.AveragePathCorrection && corrections.Any())
            {
                Engine.IncrementDepth();
                foreach (var pc in corrections)
                {
                    Engine.AddPathProcess(pc.Value.PathCalc);
                }
                Engine.IncrementDepth();
                foreach (var pc in corrections)
                {
                    Engine.AddPathProcess(pc.Value);
                }
            }

            //payoffs
            Engine.IncrementDepth();
            _payoffs = assetInstruments.ToDictionary(x => x.TradeId, y => new AssetPathPayoff(y, _currencyProvider, _calendarProvider, settings.ReportingCurrency));
            if (!settings.AvoidRegressionForBackPricing && _payoffs.Any(x => x.Value.Regressors != null))
            {
                var regressorsToAdd = _payoffs.Where(x => x.Value.Regressors != null)
                                      .SelectMany(x => x.Value.Regressors)
                                      .Distinct();

                foreach (var regressor in regressorsToAdd)
                {
                    Engine.AddPathProcess(regressor);
                    foreach (var payoff in _payoffs.Where(x => x.Value.Regressors != null))
                    {
                        if (payoff.Value.Regressors.Any(x => x == regressor))
                        {
                            payoff.Value.SetRegressor(regressor);
                        }
                    }
                }

                Engine.IncrementDepth();
            }
            foreach (var product in _payoffs)
            {
                if (settings.AvoidRegressionForBackPricing && (product.Value.AssetInstrument is BackPricingOption || product.Value.AssetInstrument is MultiPeriodBackpricingOption))
                {
                    product.Value.VanillaModel = VanillaModel;
                }

                Engine.AddPathProcess(product.Value);
            }

            var metricsNeedRegression = new[] { BaseMetric.PFE, BaseMetric.KVA, BaseMetric.CVA, BaseMetric.FVA, BaseMetric.EPE };

            //Need to calculate PFE
            if (settings.CreditSettings != null && settings.CreditSettings.ExposureDates != null && settings.ReportingCurrency != null && metricsNeedRegression.Contains(settings.CreditSettings.Metric))//setup for PFE, etc
            {
                Engine.IncrementDepth();

                switch (settings.CreditSettings.PfeRegressorType)
                {
                case PFERegressorType.MultiLinear:
                    _regressor = new LinearPortfolioValueRegressor(settings.CreditSettings.ExposureDates,
                                                                   _payoffs.Values.ToArray(), settings);
                    break;

                case PFERegressorType.MonoLinear:
                    _regressor = new MonoIndexRegressor(settings.CreditSettings.ExposureDates,
                                                        _payoffs.Values.ToArray(), settings, true);
                    break;
                }
                Engine.AddPathProcess(_regressor);
            }

            //Need to calculate expected capital
            if (settings.CreditSettings != null && settings.CreditSettings.ExposureDates != null && settings.ReportingCurrency != null && settings.CreditSettings.Metric == BaseMetric.ExpectedCapital)
            {
                Engine.IncrementDepth();
                _capitalCalc = new ExpectedCapitalCalculator(Portfolio, settings.CreditSettings.CounterpartyRiskWeighting, settings.CreditSettings.AssetIdToHedgeGroupMap, settings.ReportingCurrency, VanillaModel, settings.CreditSettings.ExposureDates);
                Engine.AddPathProcess(_capitalCalc);
            }

            Engine.SetupFeatures();
        }