turtles-own [ age ]

to setup
  ca
  cct 3 [
    set color pink
    fd 2
  ]
end

to go
  ask turtles [
    wander
    reproduce
    grow-old
  ]
  plot count turtles
  if count turtles = 0
    [ stop ]
end

to grow-old
  set age age + 1
  if (age > 50) [ die ]
end

to wander
  rt random 360
  fd 1
end

to reproduce
  if (color = pink and random 5 = 0) [
    hatch 1 [
      if random 10 > 0 [set color blue]              ;9 of 10 hatched turtles are made blue
      set age 0
    ]
  ]
end


;;This model was created as part of the project:
;;PARTICIPATORY SIMULATIONS: NETWORK-BASED DESIGN FOR SYSTEMS LEARNING IN
;;CLASSROOMS.  The project gratefully acknowledges the support of the
;;National Science Foundation ( REPP program ) -- grant number REC #9814682.

;;Copyright 2001 by Uri Wilensky. All rights reserved.

;;Permission to use, copy, or modify this software and its documentation for
;;educational and research purposes only and without fee is hereby granted,
;;provided that this copyright notice and the original authors' names appear
;;on all copies and supporting documentation. For any other uses of this
;;software, in original or modified form, including but not limited to
;;distribution in whole or in part, specific prior permission must be
;;obtained from Uri Wilensky. These programs shall not be used, rewritten,
;;or adapted as the basis of a commercial software or hardware product
;;without first obtaining appropriate licenses from Uri Wilensky. We make no
;;representations about the suitability of this software for any purpose. It
;;is provided "as is" without express or implied warranty.
@#$#@#$#@
GRAPHICS-WINDOW
326
19
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350
18
18
8.945945945945946
1
10

CC-WINDOW
6
289
302
435
Command Center

BUTTON
19
228
74
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setup
setup
NIL
1
T
OBSERVER

MONITOR
163
220
265
269
count turtles
count turtles
3
1

BUTTON
78
228
133
261
go
go
T
1
T
OBSERVER

PLOT
6
18
307
203
Population
time
count
0.0
200.0
0.0
50.0
true
false
PENS
"number" 1.0 0 -16776961 true

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WHAT IS IT?
-----------
This code example demonstrates the HATCH command.  

Blue turtles never reproduce.  Pink turtles have a one-in-five chance of reproducing at each time tick.  Each turtle's life lasts 50 ticks.  Nine out of ten baby turtles are blue.

The turtles created by HATCH are exact duplicates of their parents, so it is necessary to reset each new turtle's age to 0 inside the HATCH 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 1.0 Beta 10
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