| 1 | /* -*- mode: c++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ |
| 2 | |
| 3 | /* |
| 4 | Copyright (C) 2015 Johannes Göttker-Schnetmann |
| 5 | Copyright (C) 2015 Klaus Spanderen |
| 6 | |
| 7 | This file is part of QuantLib, a free-software/open-source library |
| 8 | for financial quantitative analysts and developers - http://quantlib.org/ |
| 9 | |
| 10 | QuantLib is free software: you can redistribute it and/or modify it |
| 11 | under the terms of the QuantLib license. You should have received a |
| 12 | copy of the license along with this program; if not, please email |
| 13 | <quantlib-dev@lists.sf.net>. The license is also available online at |
| 14 | <http://quantlib.org/license.shtml>. |
| 15 | |
| 16 | This program is distributed in the hope that it will be useful, but WITHOUT |
| 17 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
| 18 | FOR A PARTICULAR PURPOSE. See the license for more details. |
| 19 | */ |
| 20 | |
| 21 | /*! \file hestonslvprocess.hpp |
| 22 | \brief Heston stochastic local volatility process |
| 23 | */ |
| 24 | |
| 25 | #ifndef quantlib_heston_slv_process_hpp |
| 26 | #define quantlib_heston_slv_process_hpp |
| 27 | |
| 28 | #include <ql/processes/hestonprocess.hpp> |
| 29 | #include <ql/termstructures/volatility/equityfx/localvoltermstructure.hpp> |
| 30 | |
| 31 | namespace QuantLib { |
| 32 | |
| 33 | class HestonSLVProcess : public StochasticProcess { |
| 34 | public: |
| 35 | HestonSLVProcess(const ext::shared_ptr<HestonProcess>& hestonProcess, |
| 36 | ext::shared_ptr<LocalVolTermStructure> leverageFct, |
| 37 | Real mixingFactor = 1.0); |
| 38 | |
| 39 | Size size() const override { return Size(2); } |
| 40 | Size factors() const override { return Size(2); } |
| 41 | |
| 42 | void update() override; |
| 43 | |
| 44 | Array initialValues() const override { |
| 45 | return hestonProcess_->initialValues(); |
| 46 | } |
| 47 | Array apply(const Array& x0, const Array& dx) const override { |
| 48 | return hestonProcess_->apply(x0, dx); |
| 49 | } |
| 50 | |
| 51 | Array drift(Time t, const Array& x) const override; |
| 52 | Matrix diffusion(Time t, const Array& x) const override; |
| 53 | Array evolve(Time t0, const Array& x0, Time dt, const Array& dw) const override; |
| 54 | |
| 55 | Real v0() const { return v0_; } |
| 56 | Real rho() const { return rho_; } |
| 57 | Real kappa() const { return kappa_; } |
| 58 | Real theta() const { return theta_; } |
| 59 | Real sigma() const { return sigma_; } |
| 60 | Real mixingFactor() const { return mixingFactor_; } |
| 61 | ext::shared_ptr<LocalVolTermStructure> leverageFct() const { |
| 62 | return leverageFct_; |
| 63 | } |
| 64 | |
| 65 | const Handle<Quote>& s0() const { return hestonProcess_->s0(); } |
| 66 | const Handle<YieldTermStructure>& dividendYield() const { |
| 67 | return hestonProcess_->dividendYield(); |
| 68 | } |
| 69 | const Handle<YieldTermStructure>& riskFreeRate() const { |
| 70 | return hestonProcess_->riskFreeRate(); |
| 71 | } |
| 72 | |
| 73 | Time time(const Date& d) const override { return hestonProcess_->time(d); } |
| 74 | |
| 75 | private: |
| 76 | Real kappa_, theta_, sigma_, rho_, v0_, mixingFactor_, mixedSigma_; |
| 77 | |
| 78 | const ext::shared_ptr<HestonProcess> hestonProcess_; |
| 79 | const ext::shared_ptr<LocalVolTermStructure> leverageFct_; |
| 80 | |
| 81 | void setParameters(); |
| 82 | }; |
| 83 | |
| 84 | } |
| 85 | |
| 86 | #endif |
| 87 | |