;; executed once when we press the setup button
to setup
  ;; clear all turtles and patches                               
  ca   
  ;; create 20 turtles           
  crt 20            
  ask turtles 
    ;; each turtle sets its color to white
    [set color white]
  ask patches 
    ;; patches set their color to their x-coordinate
    [set pcolor pxcor]                   
end

;; forever button; thus, continuously executed
to move-turtles                         
  ask turtles  [
  ;; ask each turtle to change its color and move forward one
  set color (color - 1)     
  fd 1 wait 0.25
  ]     
end                                     

;; forever button; thus, continuously executed
to recolor-patches                                     
  ask patches
    ;; ask each patch to change its color
    [set pcolor (pcolor - 1)]      
  ;; wait a bit                      
  wait 2
end
@#$#@#$#@
GRAPHICS-WINDOW
321
10
631
341
12
12
12.0
1
10
1
1
1

CC-WINDOW
12
165
309
340
Command Center

BUTTON
58
25
113
58
setup
setup
NIL
1
T
OBSERVER
T

BUTTON
150
25
257
58
move-turtles
move-turtles
T
1
T
OBSERVER
T

BUTTON
148
77
263
110
recolor-patches
recolor-patches
T
1
T
OBSERVER
T

@#$#@#$#@
WHAT IS IT?
-----------
This demo shows how to control agentsets using agentset commands. Agentsets are exactly what the name implies -- sets of agents. In NetLogo these agents are turtles and patches. The demo shows how to control all turtles simultaneously using the "ask turtles" command, and how to control all patches simultaneously using the "ask patches" command.

The agentset can also be limited by conditions.  For example, "ask turtles with [ycor > 0] [ ... ]" would only control turtles on or above the x-axis.  Try it! 
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default
true
0
Polygon -7566196 true true 150 5 40 250 150 205 260 250

arrow
true
0
Polygon -7566196 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150

box
true
0
Polygon -7566196 true true 45 255 255 255 255 45 45 45

circle
true
0
Circle -7566196 true true 35 35 230

person
false
0
Circle -7566196 true true 155 20 63
Rectangle -7566196 true true 158 79 217 164
Polygon -7566196 true true 158 81 110 129 131 143 158 109 165 110
Polygon -7566196 true true 216 83 267 123 248 143 215 107
Polygon -7566196 true true 167 163 145 234 183 234 183 163
Polygon -7566196 true true 195 163 195 233 227 233 206 159

spacecraft
true
0
Polygon -7566196 true true 150 0 180 135 255 255 225 240 150 180 75 240 45 255 120 135

thin-arrow
true
0
Polygon -7566196 true true 150 0 0 150 120 150 120 293 180 293 180 150 300 150

truck-down
false
0
Polygon -7566196 true true 225 30 225 270 120 270 105 210 60 180 45 30 105 60 105 30
Polygon -8716033 true false 195 75 195 120 240 120 240 75
Polygon -8716033 true false 195 225 195 180 240 180 240 225

truck-left
false
0
Polygon -7566196 true true 120 135 225 135 225 210 75 210 75 165 105 165
Polygon -8716033 true false 90 210 105 225 120 210
Polygon -8716033 true false 180 210 195 225 210 210

truck-right
false
0
Polygon -7566196 true true 180 135 75 135 75 210 225 210 225 165 195 165
Polygon -8716033 true false 210 210 195 225 180 210
Polygon -8716033 true false 120 210 105 225 90 210

turtle
true
0
Polygon -7566196 true true 138 75 162 75 165 105 225 105 225 142 195 135 195 187 225 195 225 225 195 217 195 202 105 202 105 217 75 225 75 195 105 187 105 135 75 142 75 105 135 105

@#$#@#$#@
NetLogo 2.0beta4
@#$#@#$#@
setup
repeat 10 [ move-turtles ]
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