to setup
  ca
  crt 100
  ask turtles [
    ifelse random 2 = 0
      [set color yellow]  ; color half the turtles red
      [set color red]     ; the other half yellow

    rt random-float 360
    fd random 10
    ]
  ask patches [
    set pcolor green                                             ; color the patches green
  ]
end

to go  ;; turtle procedure
  rt random-float 90
  lt random-float 90
  fd 1
  ; if you're a red turtle, set the color of the patch you are on to black
  if (color = red)
    [set pcolor black]
  ; if you're a yellow turtle, set the color of the patch you are on to magenta
  if (color = yellow)
    [set pcolor magenta]
  wait 0.1                                                  ; slow it down
end
@#$#@#$#@
GRAPHICS-WINDOW
279
10
613
365
40
40
4.0
1
13
1
1
1

CC-WINDOW
6
137
269
302
Command Center

BUTTON
63
38
118
71
NIL
setup
NIL
1
T
OBSERVER
T

BUTTON
134
38
189
71
NIL
go
T
1
T
TURTLE
T

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WHAT IS IT?
-----------
This code example demonstrates Turtle-Patch communication. When a red turtle moves onto a patch, it turns the patch black.  When a yellow turtle moves onto a patch, it turns the patch magenta.

This does the same thing as the "stamp" command.
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default
true
0
Polygon -7566196 true true 150 5 40 250 150 205 260 250

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NetLogo 2.0beta4
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setup
repeat 28 [ ask turtles [ go ] ]
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