Error: Element 287 of list [0] could not be found, which is only 1 in NetLogo

Question

我想量化每只乌龟经过世界上每个补丁的次数。你知道我如何从 NetLogo 获得这些信息吗？我能够找出乌龟访问这些补丁的次数，但不知道它去了每个特定补丁的次数。例如：乌龟 0 访问了补丁 (0, 0) 2 次，补丁 (0, 1) 4 次。但是，海龟 2 访问了补丁 (0 0) 3 次，补丁 (0, 1) 3 次，依此类推。

但是，出现以下错误：找不到列表[0] 的元素287，它只有1。补丁 7 22 运行 ITEM 时出错由（匿名命令：[ id -> let item id turtle-visits set turtle-visits replace-item id turtle-visits current-num-visits + 1 ] 调用由程序 GO 调用由 'go' 按钮调用

有人可以帮助我吗？

globals [ edge-size ]
patches-own [ turtle-visits ]

to setup
  ca
  let num-turtles 1
  set edge-size 29
  resize-world 0 edge-size 0 edge-size
  let pcolors []
  set pcolors [ 85 95 ]
  ask patches [       
    set turtle-visits n-values num-turtles [0]
    set pcolor item (random 2) pcolors
  ]
  reset-ticks
end

to go
  ask turtles [
    rt random 360
    fd 1
  ]

结束

Answer 1

问题是，您用每个补丁的海龟数量初始化 turtle-visits 列表，即 num-turtles:

set turtle-visits n-values num-turtles [0]

如果您将 num-turtles 替换为 count turtles，因为您想要世界上每只海龟的值，它应该有效：

set turtle-visits n-values count turtles [0]

Error: Element 287 of list [0] could not be found, which is only 1 in NetLogo

Error: Element 287 of list [0] could not be found, which is only 1 in NetLogo

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