Netlogo: move turtles to non-occupied patches and print it

Question

I want to move turtles to one of patches not fully occupied (n-jobs-to-fill != 0). The code is

ask turtles [move-to one-of patches with [n-jobs-to-fill != 0]

After each allocation turtle-patch, n-jobs-to-fill (that works like a counter) counts one place less

ask patches [set n-jobs-to-fill n-jobs-to-fill - 1]

Can you help me to do that iteratively (for each tick) and to test it by printing each movement turlte-patch in the observer line?

Thank you

Answer 1

The part where you ask patches to update their variable should not be done with a general ask patches, as this will target all patches and either be called too seldom (if you do it just once per iteration of go) or too often (if you do it every time a specific patch receives a turtle).

To easily target the specific patch that just received a turtle, and exactly the amount of times that it receives a turtle, make the moving turtle ask its new patch to perform the update. Or even better: given that turtles can directly access the patches-own variables of the patch they are standing on, you can do:

patches-own [
  n-jobs-to-fill
]

to setup
  clear-all
  reset-ticks
  
  ask patches [
    set n-jobs-to-fill random 10
  ]
  
  create-turtles 10
end


to go
  if (not any? patches with [n-jobs-to-fill != 0]) [stop]
  
  ask turtles [
    if (any? patches with [n-jobs-to-fill != 0]) [
      move-to one-of patches with [n-jobs-to-fill != 0]
      set n-jobs-to-fill n-jobs-to-fill - 1
      
      show (word "I moved to " patch-here ", which now has " n-jobs-to-fill " jobs to fill")
    ]
  ]
  
  tick
end