混沌数学之Henon吸引子

Henon吸引子是混沌与分形的著名例子.
// http://wenku.baidu.com/view/d51372a60029bd64783e2cc0.html?re=view
class HenonAttractor : public DifferentialEquation
{
public:
    HenonAttractor()
    {
        m_StartX = 0.01f;
        m_StartY = 0.01f;
        m_StartZ = 0.0f;

        //m_ParamA = 1.28f;
        //m_ParamB = 0.3f;

        m_ParamA = 1.28f;
        m_ParamB = -0.985f;

        m_StepT = 0.01f;
    }

    void Derivative(float x, float y, float z, float& dX, float& dY, float& dZ)
    {
        //dX = (1 - m_ParamA*x*x + y - x)/m_StepT;
        //dY = (m_ParamB*x - y)/m_StepT;
        //dZ = 0.0f;

        dX = (1 - m_ParamA*x*x + m_ParamB*y /*- x*/)/m_StepT;
        dY = (x - y)/m_StepT;
        dZ = 0.0f;
    }

    bool IsValidParamA() const {return true;}
    bool IsValidParamB() const {return true;}
};