Netlogo：计算海龟拥有清单的平均值

Question

I have 2 to 10 turtles remembering a route home. The coordinate of the turtles is saved every tick to the list path .

to path-tracker
  let x xcor                     ;; gets the current coordinates
  let y ycor
  facexy x y
  setxy x y
  set path lput (list x y) path       ;; adds the coordinate pair (x,y) to the end of the path
end

When the turtles have all reached the target the procedure stops and are set back to the place where they started. Now another procedure starts and they should not follow their own path but should follow an average path of all paths.

So how do I calculate an average list of all turtle-own lists?

Answer 1

This is a very simple solution which creates a list of size path-length where the ?th element is list (coordinate) of the mean of all the turtle's 0th item (the xcordinate) of the ?th element (the coordinate) and mean of all the turtle's 1st item (the ycoordinate) of the ?th element (the coordinate):

 let path-length (length [path] of one-of turtles)
 let average n-values path-length [
   (list  (mean [(item 0 (item ? path)) ] of turtles)
          (mean [(item 1 (item ? path)) ] of turtles))]

If you don't like it being so condensed, you can use the following which accomplishes the same result.

  let average-path (list)
  foreach (n-values path-length [?])
  [
    let meanx (mean [(item 0 (item ? path)]] of turtles)
    let meany (mean [(item 1 (item ? path)]] of turtles)
    set average-path lput (list meanx meany) average-path 
  ]