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basin of attraction algorithm
is based on the dynamical system characterized by the expression, x''=a*cos(ω*t+φ)-b*(x-x3)-μ*x',
where x' is the first derivative of x with respect to time, t, and x'' is the second derivitave of x with respect to time.
The parameter values are a=5, ω=1, φ=0, b=-1 and μ=0.315.