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help for ^chaos^
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Iterating a logistic difference equation
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    ^chaos , r(^#^)^ [ ^c^onnect^(^str^) s^ymbol^(^str^)^  ]

Description
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^chaos^ iterates for 0 < r < 4 and t = 1, 2, 3, ...

        x[t+1] = r * x[t] * (1 - x[t])

starting with x[1] as a random number from the uniform distribution on
[0,1).

As r increases, the generic behaviour changes from tendency to a single
equilibrium to alternations between two equilibria, between four
equilibria, and so on, successive bifurcations leading to `chaos' for
sufficiently large r.

^chaos^ presents the user with graphs of x[t] versus t and of x[t+1]
versus x[t].


Remarks
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If there are no data in memory, ^chaos^ sets the number of observations
to 200. This is suggested as a suitable number.


Options
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^r(^#^)^ is a required option setting r: 0 < r < 4.

^connect(^ ^)^ can be used to suppress connection of data points. The
    default is ^l^.

^symbol(^ ^)^ can be used to specify a plotting symbol. The default
    is ^.^


Examples
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    . ^chaos, r(3.99)^
    . ^chaos, r(3.99) c(.) sy(o)^


Author
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         Nicholas J. Cox, University of Durham, U.K.
         n.j.cox@@durham.ac.uk