Plotting the graph for the logistic equation.

logistic_equation_2.rkt

;;; Returns a list of iterations of the logistic equation for a given 
;;; parameter r and starting point x-init.
(define (iterate-logistic-equation steps r x-init)
  (let ((xs (list x-init)))
    (for ((i (in-range 0 steps)))
      (set! xs (cons (logistic-equation r (car xs)) xs)))
    (map vector (stream->list (in-range 0 (+ 1 steps))) (reverse xs))))

;;; Plots the graph of x(n) for the given number of steps, parameter r
;;; and starting point x-init.
(define (plot-logistic-equation steps r x-init)
  (parameterize ((plot-width 400)
                 (plot-height 200)
                 (plot-font-size 11)
                 (plot-x-label "n")
                 (plot-y-label "x(n)"))
    (plot
     (lines (iterate-logistic-equation steps r x-init) 
            #:y-min 0 #:y-max 1 #:color 'blue))))