Iterated Logistic function with final-state diagram

globals [  ;; setting globals
  mylist
  axis
 ]

breed [ axis-turtles axis-turtle ] ;; these are turtles as part (i.e. axes tips) of X and Y axes
breed [ m-turtles m-turtle ]       ;; thes are turtles to be plotted on the final-state diagram

patches-own [ ;; properties of patches used to generate the coordinates axes
  alpha
  omega
]

to setup
  ca
  set mylist  list (0) (X0)  ;; setting the intial list of values
  create-axis                ;; to be iterated by logistic function
  setup-alpha                ;; setting components of X and Y axes
  setup-omega
  reset-ticks
end 

to create-axis                                        ;; creating X and Y axes
  ask patches with [ pycor = 0 ] [ set pcolor white ]
    create-axis-turtles 1 [
    set color yellow
    set size 8
    set heading -90
    setxy 0 0
  ]
    create-axis-turtles 1 [
    set color yellow
    set size 8
    set heading 90
    setxy 400 0
  ]
end 

to setup-alpha
  ask patch 5 5
  [ set plabel "0"
    set plabel-color white ]
end 

to setup-omega
  ask patch 398 5
  [ set plabel "1.0"
    set plabel-color white ]
end 

to go                                    ;; this is the procedure of iteration

 if r-parameter > 4 or X0 > 1 or X0 < 0  ;; the message that will appear if r or X0 values
  [                                      ;; are set outside the recommende range
    ask patch 350 4
    [ set plabel "ERROR: r must be between 0 and 4.0 // X0 must be between 0 and 1.0."
      set plabel-color yellow ]
      stop
  ]


  set mylist lput result mylist       ;; procedure of iteration where the results are added to a list
  if ticks >= Num-iterations [ stop ] ;; and a new turtle of red color is created with every iteration
  create-m-turtles 1 [                ;; result of the iteration serves as x-coordinates for this turtle
    set color red                     ;; according to which it is plotted on final state diagram
    set shape "circle"
    set size 5
    setxy (last mylist * 400) (0)
  ]

  if ticks <= (num-iterations) / 1.1  ;; only last 10% of turtles are plotted
  [ask m-turtles [die]]

  tick
end 

to-report result                                         ;; reporter describing the iteration procedure
  report  r-parameter * last mylist * (1 - last mylist)  ;; based on previous iteration result
end