I have a breed of turtle that owns another breed of turtle.
I need to do something like:
set my-turtle-set breed1 "owned by" breed2 with [some-attribute = 1]
So i need to put in a turtleset some turtle of the breed1 if they are owned by the turtle of the breed 2 with some characteristic.
Clarifying
Maybe thre was a misunderstanding:
I have already the breed2 owning the breed1:
breed2-own [my-owner]
and i can correctly put my breed1 turtles inside my breed2 turtles.
The problem is that i need to make hidden? some breed1 turtles basing on who onws them.
SO updating to the example (i remove my-turtle-set for being more clear):
ask breed1 ("owned by" breed2 with [some-attribute = 1]) [set hidden? true]
So the turtles already own correctly the other breed just i dont know, given a breed1 tutle, how to call its ower.
for this reason i need something like "owned by".
To Clarify even more
I have the breed2 that are part of a tree (network). At every step i set an attribute leaf? true to the leaf.
now each breed2 owns a breed1 and to every turn I need to set hidden? false toe the breed1 which are not onwed by a leaf, instead to set hidden? true to the breed1 which are owned by a leaf
If breed2 is the breed that owns, then this line:
breed2-own [my-owner]
doesn't make sense; the wording implies the relationship goes in the other direction. I'll assume you mean:
breed2-own [owned]
Then one way to solve your problem is:
ask breed1 [
set hidden? any? breed2 with [owned = myself]
]
If the number of agents in your model is fairly small, this should be fine.
If you have lots of agents, then you may start having speed problems, because in the above code, each breed1 does its own independent search through all breed2 agents.
Two possible ways to fix that:
Do what Mars suggests in his answer.
Get rid of the owned variable altogether, and use links to represent the owning relationships.
How about giving the owner breed a turtles-own variable that stores turtle-set containing the turtles it owns? You can also store a reference to the owner in each breed1, if that will make the code that uses this information simpler.
breed1-own [my-owner]
breed2-own [my-owned]
...
ask breed2 with [some-attribute = 1]
[set my-owned my-turtle-set
ask my-turtle-set [set my-owner myself]
Here myself refers to the breed2 turtle from the outer ask. (If you used self, instead, that would refer to the breed1 turtle from the inner ask.)
(Don't use both kinds of references unless you need both, though, because having breed1s and breed2s refer to each other means that when your code changes references of one kind, it has to change corresponding references of the other kind as well.)
Related
I'm trying to design a model for the spread of infection from person to environment.
Turtles have a hand contamination variable that shows the percentage of their hands that are contaminated. I'd like to give this number to patches that they're passing, but I'm getting an error saying it's a turtle-only variable.
Is it possible to give a hand contamination number to the patch?
This is part of my code:
turtles-own [hand contamination]
patches-own [p-contamination]
ask patches [set p-contamination hand-contamination]
A patch can't ever refer to turtle variables directly: What if there is more than one turtle there...which one? What if there are none?
However, a turtle can access the variables of the patch it is standing on. So you would probably do this from the turtle's point of view: I think this also makes sense, logically, since it is the turtle visiting the patch, and contaminating it.
;; turtles contaminate the patch they are standing on
ask turtles [ set p-contamination hand-contamination]
Note that if there is more than one turtle on a patch, they will overwrite each other's values. So, you may need to add the amount, or otherwise blend the two values, rather than replace it.
If there are more turtles than patches, or you really want the patch to be the thing that in control, the patch can look for turtles and acess their variables with OF:
ask patches
[ let visitors turtles-here
if any? visitors
[ set p-contamination ..some expression..
So, there it depends on your needs, and you have to decide what that value is.
There is only ever at most one turtle:
[ Contamination ] of one-of visitors
Even if many turtles, pick one at random:
[ contamination ] of one-of visitors
Use the value of the most-contaminated visitor:
(max (sentence [ contamination ] of visitors))
Average the values of contamination
(mean (sentence [ contamination ] of visitors))
...or some other expression that you choose
Again, this is all overwriting the patch variable. If you need to take the patchs' current values for that variable, you need to decide how:
If already contaminated, should it:
leave value alone
add turtle value to current value of P-Contamination
save the max of the two values
save the mean of the two values
blend them in some other way
This is the code of a 2 player game that I manipulated
o play-the-game
if (any-friends-nearby?) [gain-energy]
if (any-opponents-nearby?) [fight-opponent]
end
to-report any-friends-nearby?
report (any? (turtles-on neighbors4) with [breed = [breed] of myself])
end
to-report any-opponents-nearby?
report (any? (turtles-on neighbors4) with [breed != [breed] of myself])
end
to gain-energy
set similar-nearby count ( turtles-on neighbors4 )
with
[color = [color] of myself]
set total-nearby count (turtles-on neighbors)
;
;
if (similar-nearby >= total-nearby - similar-nearby)
[set energy energy + 5]
end
to fight-opponent
let my-breed [breed] of green-players
let my-color [color] of green-players
let opponent-breed [breed] of red-players
;
;;
ask my-breed
[check-random-winner]
end
to check-random-winner
let pick random-float 2
let winner nobody
ask turtles
[if winner = nobody
[ ifelse size > pick
[set winner self ]
[set pick pick - size] ] ]
end
to change-opponent
ask red-players
[ set breed green-players
set color green ]
end
Sorry if it's a bit long but when I setup up and then press go "ASK expected input to be an agent or agentset but got the list [green-players...]"
How can I fix this?
Also I'm very new to Netlogo and StackOverflow, apologies if I haven't asked my question properly.
The error message tells you that you are passing a list (more specifically, a list of breeds) to ask, when it comes to ask my-breed.
This is because the my-breed local variable is determined by
let my-breed [breed] of green-players
Let's see what we have there:
breed is a turtles-own variable: it holds the turtle's breed, and being an agents' variable can be used as a reported in the of construct (see below).
of is a reporter: it takes a reporter (normally an agents' variable) on its left (in your case: breed) and either an agent or an agentset on its right (in your case: green-players). What of reports (i.e. what it outputs) is...
... a single value if there is an agent on the right.
... a list of values if there is an agentset on the right*.
*Think about it: if I ask the color of your eyes (you are a single person, i.e. a single agent), you will tell me a single color. But if I ask the color of your friends' eyes (your friends are a group of people, i.e. an agentset), the only way for you to answer my question is to tell me a list of colors.
green-players is an agentset: all of the agents whose breed is green-players (note that for NetLogo green-players is an agentset even if it contains 1 or 0 agents).
From this, we can see that in this case of reports a list of breeds, because it reports the breed of every agent that is part of green-players, hence it will report the list [green-players green-players green-players green-players ... ] which is as long as the number of green-players in the model. You can verify this by clicking setup and then running [breed] of green-players in the Command Center.
This is a list of breeds (which can also be seen as a list of agentsets), which is not an agent or an agentset (which are the only possible targets of ask).
((note that the exact same thing happens with let my-color [color] of green-players and let opponent-breed [breed] of red-players))
So, how do you construct an agentset based on a variable? The most common way to do it is by using with (read here why).
But how can you fix your code? I don't know because I don't understand what you want to achieve.
I am not sure how you would want to use it in the code you posted, as I'm not even sure you need to use ask in fight-opponent (let alone ask an agentset).
Your fight-opponent procedure is such that, apart from the problem we just discussed, the "my-" things (i.e. my-breed and my-color) always refer to the green players while opponent-breed always refers to the red players - even if fight-opponent is run by a red player! And also, it is not clear what you want to achieve with the check-random-winner procedure and if you want this procedure to be ran by an entire breed. These things make it quite confusing to understand how you could want to fix the fight-opponent procedure.
For example: who do you want to run the check-random-winner command?
A combination of two things would be beneficial: develop your model one step at a time and make sure that every new little piece of code does exactly what you expect it to do; also, when you ask for how to fix something it is useful that you explain what you want your code to do. By doing these two things I believe it will be a lot easier to answer your questions
I am brand new to Netlogo and am coding a world with caching animals. They will go to their caches (I set them as blue patches) if their energy value falls below 10. They can find these caches based on a random 'memory' value given to them which is used as an in-radius value. That way, they will face and go towards a cache within their in-radius memory if they are about to die. I am starting to incorporate a home-base system where the turtle remains in a smaller area with their own caches. Does anyone know how I can make a patch belong to an individual turtle? This would allow turtles to have their specific caches in their territory. I have looked into using links and breeds, but links are only between turtles and making the individual breeds for the 50+ turtles at a time seems ineffective and complex. I apologize I don't have any code attempting to have a cache (patch) belong to a turtle, I don't know where to start. Any ideas?
If you want a turtle to remember anything (patches or income or anything else), then you need to assign a variable in a turtles-own statement and then set the value appropriately. Here's some example code fragments. They won't work, and you actual code would likely look a lot different because you will need some design about the conditions under which a cache will be assigned, but they show you what a variable solution looks like.
turtles-own
[ my-caches
]
set my-caches (patch-set my-caches patch-here) ; code when a turtle finds a new cache site
If you want a patch that belongs to a turtle to make that patch unavailable to other turtles, then also set up a patch variable to store its owner.
patches-own
[ my-owner
]
ask turtles
[ if [my-owner] of patch-here = nobody [set my-caches (patch-set my-caches patch-here)]
ask patch-here [set my-owner myself]
]
I suggest you do several NetLogo tutorials, then look at some library models (and understand them) before starting your own model. You need to understand basic concepts like turtles/patches, variables, ticks before trying to build a model.
I have a programme that sets up a number of different breeds of turtles. Each breed needs to have a leader turtle and a follower turtle. I have assigned these as global variables as they come up a lot in the code further down.
I need to assign these variables to turtles in the breeds and then create a link from the leader to the follower. There are a lot of conditions in the interface that determine how many and which breeds are created so i cannot assign by turtle number.
I am receiving an error (not all of the time) 'turtle cannot link with itself' which i presume occurs when they overwrite the first set command and assign the same turtle to the two variables. Does anybody know a condition i can put in that will allow it to set up everytime without the error. ( I have tried if statements, is-turtle?, one-of other, other)
breed [flinks flink] ;; linked turtles that will turn away from sources
globals [
flink-leader
flink-followers]
to set-up
clear-all
setup-turtles
reset-ticks
end
to setup-turtles
create-flinks 2 [
set flink-leader one-of flinks
set flink-followers one-of other flinks
ask flink-followers [create-link-with flink-leader]
ask flink-followers [set color pink]
ask flink-leader [
setxy 10 4]
ask flink-followers [
setxy 19.5 4]
]
end
to go
fd 1
end
There would be many different ways to approach this. Here is one that doesn't stray too far from the code you have provided:
to setup-turtles
create-flinks 2
set flink-leader one-of flinks
ask flink-leader [
set flink-followers one-of other flinks
setxy 10 4
]
ask flink-followers [
create-link-with flink-leader
setxy 19.5 4
set color pink
]
end
Note that your intuition about using other to make sure that the follower(s) is/are different from the leader was correct.
To understand what was going on, you need to grasp the notion of "context" in NetLogo. Some primitives, like ask, of and create-turtles, are "context switching": one of their argument is a code block (the part between [ and ]) that runs in the context of a particular turtle. Other primitives depend on the context in which the code is running: the primitive named other, for example, will report all the agents from a given agentset, except the one in the context of which the block is running.
In your version, you wrapped most of the code inside a code block provided for create-flinks. That meant that the code block was run once for each turtle that was created. So your calls to set flink-leader, set flink-followers and so on were all run twice, each time in a different turtle context. Can you see how that was messing things up?
Keeping track of the different context in NetLogo can be challenging at first (the frequent confusion between self/myself being a case in point), but once you get it, it should become easy and natural.
One last point as an addendum. You say:
i cannot assign by turtle number
Good! Never¹ assign anything by turtle number! It leads to brittle, error prone, more complex, less general, unnetlogoish code. If you think you need to use turtle numbers anywhere in your code, come ask another question here. Someone will most likely suggest a better way to do it.
¹ Well, almost never.
I want to add an agenset of turtles to the variable TurtlesICanSee of a certain turtle that depends on that turtles properties. For instance, in one application I want to add only the turtle itself to TurtlesICanSee, in another application I want to add the two turtles (if there are any) with adjacent who-numbers (the turtle's own who-number + or - 1).
If I can figure out the first application by using who-numbers I think I can extend that to second application. However, I cannot figure out the first.
I tried
ask turtles [
set TheTurtlesICanSee turtles with [who = ([who] of self)]
]
but this fills the TheTurtlesICanSee of each turtle with every turtle.
I think I understand why; NetLogo thinks that I want every turtle x that has the same who-number as itself (x), i.e. every turtle. But I don't. For every turtle x I want every turtle y that has the same who-number as x.
Can anyone help me with this? Note that the solution that I need to the first application is one that can be generalized to the second. So not any way of adding a turtle to one of its own variables will do. I need a form of self-reference involving who (or a good argument against doing it this way I guess, but preferably the former).
Your code needs only a slight alteration to work, as follows:
ask turtles [ set TheTurtlesICanSee turtles with [who = [who] of myself] ]
Note the substitution of myself for self; http://ccl.northwestern.edu/netlogo/docs/dictionary.html#myself has an explanation of the difference.
But actually there's no need to involve who numbers. It's almost never necessary to use who numbers in NetLogo; there's almost always a simpler, more direct solution. A simpler solution is:
ask turtles [ set TheTurtlesICanSee turtles with [self = myself] ]
But actually it isn't necessary to use with at all. We can use turtle-set to build the desired agentset directly:
ask turtles [ set TheTurtlesICanSee (turtle-set self) ]
This is the solution I would recommend, for clarity and brevity, but also because it will run faster, since it doesn't involve iterating over the set of all turtles, as the with-based solutions do.