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Diffstat (limited to 'chaos/src/lorenz.hpp')
| -rw-r--r-- | chaos/src/lorenz.hpp | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/chaos/src/lorenz.hpp b/chaos/src/lorenz.hpp new file mode 100644 index 0000000..cf0fa14 --- /dev/null +++ b/chaos/src/lorenz.hpp @@ -0,0 +1,101 @@ +// +// +// chaos~ +// Copyright (C) 2004 Tim Blechmann +// +// This program is free software; you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation; either version 2 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program; see the file COPYING. If not, write to +// the Free Software Foundation, Inc., 59 Temple Place - Suite 330, +// Boston, MA 02111-1307, USA. + +#include "ode_base.hpp" + +// lorenz model: dx1/dt = sigma * (x2 - x1) +// dx2/dt = - x1 * x3 + r * x1 - x2 +// dx3/dt = x1 * x2 - b * x3 +// taken from Willi-Hans Steeb: Chaos and Fractals + +class lorenz + : public ode_base<3> +{ +public: + lorenz() + { + CHAOS_PAR_INIT(method,0); + CHAOS_PAR_INIT(dt,0.01); + + CHAOS_SYS_INIT(x1,0.8,0); + CHAOS_SYS_INIT(x2,0.7,1); + CHAOS_SYS_INIT(x3,0.6,2); + + CHAOS_PAR_INIT(sigma,16); + CHAOS_PAR_INIT(b,4); + CHAOS_PAR_INIT(r,40); + } + + ~lorenz() + { + } + + virtual void m_system(data_t* deriv, data_t* data) + { + data_t x1 = data[0], x2 = data[1], x3 = data[2]; + + deriv[0] = CHAOS_PARAMETER(sigma) * (x2 - x1); + deriv[1] = - x1 * x3 + CHAOS_PARAMETER(r) * x1 - x2; + deriv[2] = x1 * x2 - CHAOS_PARAMETER(b) * x3; + } + + + /* function has a fix point for x1 == x2 == x3 == 0 */ + virtual void m_verify() + { + if (m_data[0] == 0 && m_data[1] == 0 && m_data[2] == 0) + for (int i = 0; i != 3; ++i) + m_data[i] = rand_range(0,3); + } + + + CHAOS_SYSVAR_FUNCS(x1, 0); + CHAOS_SYSVAR_FUNCS(x2, 1); + CHAOS_SYSVAR_FUNCS(x3, 2); + + CHAOS_SYSPAR_FUNCS_PRED(sigma, m_pred); + CHAOS_SYSPAR_FUNCS_PRED(b, m_pred); + CHAOS_SYSPAR_FUNCS_PRED(r, m_pred); + + bool m_pred (t_float f) + { + return (f > 0); + } + +}; + + +#define LORENZ_CALLBACKS \ +ODE_CALLBACKS; \ +CHAOS_SYS_CALLBACKS(x1); \ +CHAOS_SYS_CALLBACKS(x2); \ +CHAOS_SYS_CALLBACKS(x3); \ +CHAOS_SYS_CALLBACKS(sigma); \ +CHAOS_SYS_CALLBACKS(r); \ +CHAOS_SYS_CALLBACKS(b); + +#define LORENZ_ATTRIBUTES \ +ODE_ATTRIBUTES; \ +CHAOS_SYS_ATTRIBUTE(x1); \ +CHAOS_SYS_ATTRIBUTE(x2); \ +CHAOS_SYS_ATTRIBUTE(x3); \ +CHAOS_SYS_ATTRIBUTE(sigma); \ +CHAOS_SYS_ATTRIBUTE(r); \ +CHAOS_SYS_ATTRIBUTE(b); |