turtle粘合patch的运动问题

lincw

请问：
随机产生的turtle 已经在patch的坐标上上下左右一格格运动，当turtle碰到一个随即分布的patch以一定概率粘合,patch变色，其他turtle经过也还是以一定概率粘合的，粘合后turtle的能量就会转变到patch上，并且以一定速率消耗它，怎么编写这个过程？下面是我编写的，运行时就出错了。怎么改正呢？

( I* u5 }) ~5 y
turtles-own [ energy ]
to setup
clear-all
set-default-shape turtles "square"
crt nutrition
ask turtles[
    set color white
    setxy random-pxcor random-pycor]
* X" c  p6 V+ i' {  ?  
  s% ?6 w+ [4 n# c& e9 h; \ask n-of microbes-initialization patches
    [ set pcolor green]
ask turtles [set energy  1]
end

to go
    ask turtles [set heading 90 * random 4    fd 1]
) u, ~5 L5 q& d! m% W  c6 w* V     ask patches  with [ any? turtles-here]
    [  if pcolor = green and random 100 < chance-of-congregating [tt ]]
1 r. l# d& a1 q0 k) R     ask turtles [ if energy = 0  [die ]]
end
5 X( O. Y2 w; |4 z
to tt
5 P4 z2 [, S; |  x% Lask patches [set pcolor gray ]
ask  turtles [set energy energy - 1]
end

lincw

谢谢楼上两位，后来自己用两种turtle来表示暂时把问题解决了，以后再出现难题再向你们请教啊