I just started learning netlogo a couple of days ago and would appreciate some help. I have a list called "distance", which gives me the distance from each patch in a given radius to a current patch. I want to plug in each value of "distance" into the following, to get an "attractiveness" value for each patch:

Patch attractiveness = exp ((distance / 800) * (log e (.2 / 1)))]

I would like to store these values in another list called "patch_attractiveness." I think I should use either map or foreach, but I do get the error "Nothing named d has been defined." Below is what I have tried:

let Patch_attractiveness map [d -> distance] exp ((d / 800) * (log e (.2 / 1)))]

I think my confusion is primarily with how to use anonymous procedures.

CodePudding user response：

The problem was where you placed distance and the fact that you have two closing brackets but only 1 opening bracket. When using map, the order goes; map [anonymous procedure] list

let Patch_attractiveness map  [d -> exp ((d / 800) * (log e (.2 / 1)))] distance

Foreach is a bit different in the order and also requires some extra steps to make the list you need. For foreach, it goes: foreach list [anonymous procedure]. Foreach does not return a list so you need to make that one yourself.

let Patch_attractiveness []
foreach distance [d -> 
   let this-attractiveness exp ((d / 800) * (log e (.2 / 1)))
   set Patch-attractiveness lput this-attractiveness Patch-attractiveness
] 

Anonymous procedures can feel a bit weird so I encourage you to just keep playing around with them to get used to the syntax.