1/* -*- mode: c++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2
3/*
4 Copyright (C) 2004, 2005 StatPro Italia srl
5
6 This file is part of QuantLib, a free-software/open-source library
7 for financial quantitative analysts and developers - http://quantlib.org/
8
9 QuantLib is free software: you can redistribute it and/or modify it
10 under the terms of the QuantLib license. You should have received a
11 copy of the license along with this program; if not, please email
12 <quantlib-dev@lists.sf.net>. The license is also available online at
13 <http://quantlib.org/license.shtml>.
14
15 This program is distributed in the hope that it will be useful, but WITHOUT
16 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17 FOR A PARTICULAR PURPOSE. See the license for more details.
18*/
19
20/*! \file eulerdiscretization.hpp
21 \brief Euler discretization for stochastic processes
22*/
23
24#ifndef quantlib_euler_discretization_hpp
25#define quantlib_euler_discretization_hpp
26
27#include <ql/stochasticprocess.hpp>
28
29namespace QuantLib {
30
31 //! Euler discretization for stochastic processes
32 /*! \ingroup processes */
33 class EulerDiscretization
34 : public StochasticProcess::discretization,
35 public StochasticProcess1D::discretization {
36 public:
37
38 /*! Returns an approximation of the drift defined as
39 \f$ \mu(t_0, \mathbf{x}_0) \Delta t \f$.
40 */
41 Array drift(const StochasticProcess&, Time t0, const Array& x0, Time dt) const override;
42 /*! Returns an approximation of the drift defined as
43 \f$ \mu(t_0, x_0) \Delta t \f$.
44 */
45 Real drift(const StochasticProcess1D&, Time t0, Real x0, Time dt) const override;
46
47 /*! Returns an approximation of the diffusion defined as
48 \f$ \sigma(t_0, \mathbf{x}_0) \sqrt{\Delta t} \f$.
49 */
50 Matrix diffusion(const StochasticProcess&, Time t0, const Array& x0, Time dt) const override;
51 /*! Returns an approximation of the diffusion defined as
52 \f$ \sigma(t_0, x_0) \sqrt{\Delta t} \f$.
53 */
54 Real diffusion(const StochasticProcess1D&, Time t0, Real x0, Time dt) const override;
55
56 /*! Returns an approximation of the covariance defined as
57 \f$ \sigma(t_0, \mathbf{x}_0)^2 \Delta t \f$.
58 */
59 Matrix covariance(const StochasticProcess&, Time t0, const Array& x0, Time dt) const override;
60 /*! Returns an approximation of the variance defined as
61 \f$ \sigma(t_0, x_0)^2 \Delta t \f$.
62 */
63 Real variance(const StochasticProcess1D&, Time t0, Real x0, Time dt) const override;
64 };
65
66}
67
68
69#endif
70
71

source code of quantlib/ql/processes/eulerdiscretization.hpp