public virtual void pointAndParameterFx()
        {
            ImmutableRatesProvider test        = ImmutableRatesProvider.builder(VAL_DATE).fxRateProvider(FX_MATRIX).discountCurve(GBP, DISCOUNT_CURVE_GBP).discountCurve(USD, DISCOUNT_CURVE_USD).build();
            ImmutableRatesProvider test_gbp_up = ImmutableRatesProvider.builder(VAL_DATE).fxRateProvider(FX_MATRIX).discountCurve(GBP, DISCOUNT_CURVE_GBP_UP).discountCurve(USD, DISCOUNT_CURVE_USD).build();
            ImmutableRatesProvider test_gbp_dw = ImmutableRatesProvider.builder(VAL_DATE).fxRateProvider(FX_MATRIX).discountCurve(GBP, DISCOUNT_CURVE_GBP_DOWN).discountCurve(USD, DISCOUNT_CURVE_USD).build();
            ImmutableRatesProvider test_usd_up = ImmutableRatesProvider.builder(VAL_DATE).fxRateProvider(FX_MATRIX).discountCurve(GBP, DISCOUNT_CURVE_GBP).discountCurve(USD, DISCOUNT_CURVE_USD_UP).build();
            ImmutableRatesProvider test_usd_dw = ImmutableRatesProvider.builder(VAL_DATE).fxRateProvider(FX_MATRIX).discountCurve(GBP, DISCOUNT_CURVE_GBP).discountCurve(USD, DISCOUNT_CURVE_USD_DOWN).build();
            LocalDate matuirtyDate             = GBP_USD_WM.calculateMaturityFromFixing(VAL_DATE, REF_DATA);
            double    maturityTime             = DAY_COUNT.relativeYearFraction(VAL_DATE, matuirtyDate);
            // GBP based
            FxIndexObservation      obs = FxIndexObservation.of(GBP_USD_WM, VAL_DATE, REF_DATA);
            PointSensitivityBuilder sensiBuildCmpGBP = test.fxIndexRates(GBP_USD_WM).ratePointSensitivity(obs, GBP);
            FxIndexSensitivity      sensiBuildExpGBP = FxIndexSensitivity.of(obs, GBP, USD, 1.0);

            assertTrue(sensiBuildCmpGBP.Equals(sensiBuildExpGBP));
            double sense_gbp1 = 0.5 * (test_gbp_up.fxIndexRates(GBP_USD_WM).rate(obs, GBP) - test_gbp_dw.fxIndexRates(GBP_USD_WM).rate(obs, GBP)) / EPS_FD * (-maturityTime * GBP_DSC);
            double sense_usd1 = 0.5 * (test_usd_up.fxIndexRates(GBP_USD_WM).rate(obs, GBP) - test_usd_dw.fxIndexRates(GBP_USD_WM).rate(obs, GBP)) / EPS_FD * (-maturityTime * USD_DSC);
            PointSensitivityBuilder sensiBuildDecGBP = ZeroRateSensitivity.of(GBP, maturityTime, USD, sense_gbp1);

            sensiBuildDecGBP = sensiBuildDecGBP.combinedWith(ZeroRateSensitivity.of(USD, maturityTime, USD, sense_usd1));
            CurrencyParameterSensitivities paramSensiCmpGBP = test.parameterSensitivity(sensiBuildCmpGBP.build().normalized());
            CurrencyParameterSensitivities paramSensiExpGBP = test.parameterSensitivity(sensiBuildDecGBP.build().normalized());

            assertTrue(paramSensiCmpGBP.equalWithTolerance(paramSensiExpGBP, EPS_FD));
            // USD based
            PointSensitivityBuilder sensiBuildCmpUSD = test.fxIndexRates(GBP_USD_WM).ratePointSensitivity(obs, USD);
            FxIndexSensitivity      sensiBuildExpUSD = FxIndexSensitivity.of(obs, USD, GBP, 1.0);

            assertTrue(sensiBuildCmpUSD.Equals(sensiBuildExpUSD));
            double sense_gbp2 = 0.5 * (test_gbp_up.fxIndexRates(GBP_USD_WM).rate(obs, USD) - test_gbp_dw.fxIndexRates(GBP_USD_WM).rate(obs, USD)) / EPS_FD * (-maturityTime * GBP_DSC);
            double sense_usd2 = 0.5 * (test_usd_up.fxIndexRates(GBP_USD_WM).rate(obs, USD) - test_usd_dw.fxIndexRates(GBP_USD_WM).rate(obs, USD)) / EPS_FD * (-maturityTime * USD_DSC);
            PointSensitivityBuilder sensiBuildDecUSD = ZeroRateSensitivity.of(GBP, maturityTime, GBP, sense_gbp2);

            sensiBuildDecUSD = sensiBuildDecUSD.combinedWith(ZeroRateSensitivity.of(USD, maturityTime, GBP, sense_usd2));
            CurrencyParameterSensitivities paramSensiCmpUSD = test.parameterSensitivity(sensiBuildCmpUSD.build().normalized());
            CurrencyParameterSensitivities paramSensiExpUSD = test.parameterSensitivity(sensiBuildDecUSD.build().normalized());

            assertTrue(paramSensiCmpUSD.equalWithTolerance(paramSensiExpUSD, EPS_FD));
        }
        public virtual void pointAndParameterPriceIndex()
        {
            double                 eps           = 1.0e-13;
            LocalDate              valuationDate = LocalDate.of(2014, 1, 22);
            DoubleArray            x             = DoubleArray.of(0.5, 1.0, 2.0);
            DoubleArray            y             = DoubleArray.of(224.2, 262.6, 277.5);
            CurveInterpolator      interp        = CurveInterpolators.NATURAL_CUBIC_SPLINE;
            string                 curveName     = "GB_RPI_CURVE";
            InterpolatedNodalCurve interpCurve   = InterpolatedNodalCurve.of(Curves.prices(curveName), x, y, interp);
            ImmutableRatesProvider provider      = ImmutableRatesProvider.builder(VAL_DATE).priceIndexCurve(GB_RPI, interpCurve).timeSeries(GB_RPI, LocalDateDoubleTimeSeries.of(date(2013, 11, 30), 200)).build();

            double    pointSensiValue = 2.5;
            YearMonth refMonth        = YearMonth.from(valuationDate.plusMonths(9));
            InflationRateSensitivity       pointSensi = InflationRateSensitivity.of(PriceIndexObservation.of(GB_RPI, refMonth), pointSensiValue);
            CurrencyParameterSensitivities computed   = provider.parameterSensitivity(pointSensi.build());
            DoubleArray sensiComputed = computed.Sensitivities.get(0).Sensitivity;

            InflationRateSensitivity pointSensi1 = InflationRateSensitivity.of(PriceIndexObservation.of(GB_RPI, refMonth), 1);
            DoubleArray sensiExpectedUnit        = provider.priceIndexValues(GB_RPI).parameterSensitivity(pointSensi1).Sensitivities.get(0).Sensitivity;

            assertTrue(sensiComputed.equalWithTolerance(sensiExpectedUnit.multipliedBy(pointSensiValue), eps));
        }