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powered by NetLogo

view/download model file: AntPiles.nlogo

WHAT IS IT?

This is a demo of how simple commands can result in complex behavior.

An ant is colored white if he is carrying nothing, and blue if he is carrying food.
Empty ground is black, and food is yellow.

Each ant knows only a few commands…
Wander randomly,
If you come across some food, do one of two things..
If you are not carrying food, pick it up.
If you are already carrying food, drop the food.

HOW TO USE IT

The slider for “number of ants” selects how many ants you want to walk around. A good number is 500.
The slider for “ground-cover” selects the percentage of ground covered by food. A good value is 10%.
The “setup” draws the world, the ants and distibutes the food.
The “go” button starts the simulation.
You can make use of the slider at the top to control the speed of the simulation.

THINGS TO NOTICE

The ants will quickly start forming piles of food. As the piles grow, they will assimilate any smalls piles close by. Small piles will disappear as the larger ones grow. Eventually there will only be one large pile.

THINGS TO TRY

Varying the percentage of ground cover and the number of ants.

EXTENDING THE MODEL

Next will be to have ants collect different types of food and stack them in separate piles. This will be a form of sorting.

NETLOGO FEATURES

RELATED MODELS

Termites by Uri Wilensky

HOW TO CITE

CODE

;;piles-versian 14- compleate new rewrite

breed [ants ant]
ants-own [need-to-drop]

to setup
  ;; (for this model to work with NetLogo's new plotting features,
  ;; __clear-all-and-reset-ticks should be replaced with clear-all at
  ;; the beginning of your setup procedure and reset-ticks at the end
  ;; of the procedure.)
  __clear-all-and-reset-ticks
  set-default-shape ants "bug"
  ask patches
  [ if random-float 100 < ground-cover
    [ set pcolor yellow ] ]
  create-ants number-of-ants [
    set color white
    setxy random-xcor random-ycor
    set size 5  
  ]
end

to go  ;; ant procedure
  ifelse pcolor = yellow  ; ant is standing on food
  [   if color = blue  ;;a blue ant is carrying
       [ 
         set need-to-drop 1
         walk
       ]   
       if color = white  ; ant is not carrying
       [
        set pcolor black
        set color blue
        walk
       ]  
  ]  ;;end of if pcolor is yellow
;;This means the ant is on ground, not food
  [
      ifelse need-to-drop = 1
      [
       set pcolor yellow
       set color white
       set need-to-drop 0
        walk
        fd 20
      ]  
      [
        walk
        ]
  ]  ;;end of if pcolor is yellow else
end

to walk ; ant walking procedure
  rt random 50
  lt random 50
  fd 1
end