| 1 | /* -*- mode: c++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ |
| 2 | |
| 3 | /* |
| 4 | Copyright (C) 2003 Ferdinando Ametrano |
| 5 | Copyright (C) 2001, 2002, 2003 Sadruddin Rejeb |
| 6 | Copyright (C) 2004, 2005 StatPro Italia srl |
| 7 | |
| 8 | This file is part of QuantLib, a free-software/open-source library |
| 9 | for financial quantitative analysts and developers - http://quantlib.org/ |
| 10 | |
| 11 | QuantLib is free software: you can redistribute it and/or modify it |
| 12 | under the terms of the QuantLib license. You should have received a |
| 13 | copy of the license along with this program; if not, please email |
| 14 | <quantlib-dev@lists.sf.net>. The license is also available online at |
| 15 | <http://quantlib.org/license.shtml>. |
| 16 | |
| 17 | This program is distributed in the hope that it will be useful, but WITHOUT |
| 18 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
| 19 | FOR A PARTICULAR PURPOSE. See the license for more details. |
| 20 | */ |
| 21 | |
| 22 | /*! \file geometricbrownianprocess.hpp |
| 23 | \brief Geometric Brownian-motion process |
| 24 | */ |
| 25 | |
| 26 | #ifndef quantlib_geometric_brownian_process_hpp |
| 27 | #define quantlib_geometric_brownian_process_hpp |
| 28 | |
| 29 | #include <ql/stochasticprocess.hpp> |
| 30 | |
| 31 | namespace QuantLib { |
| 32 | |
| 33 | //! Geometric brownian-motion process |
| 34 | /*! This class describes the stochastic process governed by |
| 35 | \f[ |
| 36 | dS(t, S)= \mu S dt + \sigma S dW_t. |
| 37 | \f] |
| 38 | |
| 39 | \ingroup processes |
| 40 | */ |
| 41 | class GeometricBrownianMotionProcess : public StochasticProcess1D { |
| 42 | public: |
| 43 | GeometricBrownianMotionProcess(double initialValue, |
| 44 | double mue, |
| 45 | double sigma); |
| 46 | Real x0() const override; |
| 47 | Real drift(Time t, Real x) const override; |
| 48 | Real diffusion(Time t, Real x) const override; |
| 49 | |
| 50 | protected: |
| 51 | double initialValue_; |
| 52 | double mue_; |
| 53 | double sigma_; |
| 54 | }; |
| 55 | |
| 56 | } |
| 57 | |
| 58 | |
| 59 | #endif |
| 60 | |