I have several turtles each with three variables opinion1, opinion2 and opinion3. I need them to:
identify which of these three variables has the highest value
find another turtle in their network with a value at least as high
as the one found in 1.
update its own value found in 1. with
respect to that of the turtle found in 2.
What I have done doesn't really work because it only updates looking at o1 without really having a look at which of the tree (opinion1, opinion2 or opinion3) is the highest and THEN looking for a neighbour.
to update-opinion
ask turtles [
let my-nearby-turtles nw:turtles-in-radius 1
let my-opinion1 opinion1
set neighbour one-of my-nearby-turtles with [ opinion1 > my-opinion1 ]
if neighbour != nobody [
let opinion_n [opinion1] of neighbour
set opinion1 ((opinion1 + opinion_n) / (2))
]
]
end
I don't know a simple way to do this with unique variables like opinion1 etc, but maybe having a list of opinions instead of individual variables for each opinion will work. For example, with this setup:
extensions [ nw ]
turtles-own [
opinions
]
to setup
ca
resize-world -5 5 -5 5
set-patch-size 30
crt 30 [
set shape "dot"
set opinions n-values 3 [ precision random-float 10 2]
set color scale-color blue sum opinions -5 35
while [ any? other turtles-here ] [
move-to one-of neighbors4
]
]
ask turtles [
create-links-with turtles-on neighbors4
]
reset-ticks
end
You get something like this:
Where each turtle has an opinions list variable that is three items long. Now, you can have each turtle determine its highest opinion value using max, get that maximum values index position in the list using position, and then query that turtle's neighbors to see if any of them have a higher value in the same index position. If they do, modify your asking turtles opinions list using replace-item to be the average of the two values:
to go
ask turtles [
; Get adjacent turtles
let my-nearby-turtles nw:turtles-in-radius 1
; Identify the highest highest value variable of
; the current turtle, and get its list position
let my-opinion max opinions
let my-op-ind position my-opinion opinions
; Pick one of the turtles whose value in the same indexed
; position is higher than my-opinion
let influence one-of my-nearby-turtles with [
item my-op-ind opinions > my-opinion
]
; If that turtle exists, update my own opinions list as appropriate
if influence != nobody [
let new-opinion precision (
( [ item my-op-ind opinions ] of influence + my-opinion ) / 2
) 2
set opinions replace-item my-op-ind opinions new-opinion
]
set color scale-color blue sum opinions -5 35
]
tick
end
Hopefully that is sort of on the right track, not sure if a list will work for what you need. If you must have the variables as standalone values at each tick, I suppose you could convert them to a list then follow the procedure above. If you only need them for output, you could just update your unique variables as needed based on the values in the list (as long as you are consistent with the order).
Related
This is my first Netlogo script and I am a complete beginner and need help in setting the xy coordinates for my turtles which are boats. I wish the boats to be positioned across the top of the world (in a 30 x 30 world, with origin in the bottom left-hand corner). The number of boats is selected by a slider, ranging from 1 to 4. After looking at other questions & answers, I have tried the following code, but cannot get it to work, either "expected closing bracket" or "FOREACH expected at least 2 inputs, a list and an anonymous command" errors.
create-boats N-boats ;; create the boats
[set color red ;; give them a color, a size and shape
set size 1
set shape "arrow"
(foreach [ 0 1 2 3 ] [6 12 18 24] [28 28 28 28] [ xy -> boats [ setxy item 0 xy item 1 xy ] ] )
set heading 180]]]
I also tried "set xcor one-of [6 12]", but sometimes get the boats lined up on top of each other, so I wish to specify the exact coordinates. Many thanks.
Do they have to be equally spaced? Or just anywhere along the top? If anywhere along the top, you are better off choosing 4 random patches in that row and getting each of them to sprout a boat. Something like (not tested):
ask n-of N-boats patches with [pycor = max-pycor]
[ sprout 1
[ set color red
set heading 180
set shape "arrow"
]
]
Just as a general newbie tip with NetLogo, if you are using foreach then you should immediately think about whether what you really want is some sort of agentset. It's particularly common for people coming from some other coding background to try and do things in for loops that are better handled as agentsets in NetLogo.
First, to answer your syntax issues:
Remember that the code in brackets after CREATE-TURTLES is run by a single turtle. After all the turtles are created, each turtle runs the code, one-at-a-time. It looks like you're trying to position all the turtles. That's probably not what you meant.
Second: look at the FOREACH.
( foreach [ 0 1 2 3 ] [6 12 18 24] [28 28 28 28] [ xy -> boats [ setxy item 0 xy item 1 xy ] ] )
You've got the foreach in ( and ) -- that's good.
You've got THREE separate lists as input -- that's fine, too, but looks like maybe you meant that to be one list? Not sure.
Your anonymous procedure has only ONE input: xy. That's a problem, since you have THREE lists as input.
You are referring to ITEM 0 and ITEM 1... which doesn't make a lot of sense at that point, unless you passed a list of lists, but no... still not.
Finally, it looks like you meant to ask boats but if you did, since this is inside the create-turtles code block, this is already being excuted by a boat. So, this boat will ask all boats to do something. If this was otherwise correct, you'd just do the boat commands--you are essentially already inside an "ask".
So, this is not ideal, in any case. Let's start at the top.
Three Ways to Set Turtle Location
If you want to put turtles at specific x and y coordinates, you have a few choices. Here's three:
Use Math based on the value of WHO to calculate the coordinates.
(Or a counter, if you want to keep your model "who-agnostic")
Use a set of patches (probably created using Math, too.) The patches SPROUT the turtles.
Use a List of coordinates. Each turtle pulls its location from the list.
A Note on the Examples.
All the below examples focus on setting the position. After the boats
are created, the boats are asked to run a procedure called
apply-boat-properties, which is where things like color, heading,
size, and other properties would be set. This is to remove clutter
from the examples. It also makes it quite easy to find where the
properties are being set.
to apply-boat-properties
;; run by a boat
set heading 180
set shape "arrow"
set color gray
end
Math (aka "calculated position")
You can do this is the locations are in a pattern that can be calculated. This can be easy to do, but can also be hard and require a lot of tweaking and experimentation to get just right. The weird NetLogo world geometry can sometimes be confusing.
Simple Example of Calculated Positioning
to make-fleet [ #fleet-count ]
create-boats #fleet-count
[ setxy (min-pxcor + 6 + who * 6) max-pycor
apply-boat-properties
]
Elaborate Example of Calculated Positioning
Varies the gap between boats automatically.
The boats are located without regard to patch centers,
unless "$center-on-patches?" is set to true
WHO is not used in the calculations. This ensures the math comes out right, even if other turtles already exist in the model.
to make-fleet [ $fleet-count $center-on-patches? ]
;; requires breed [ boats boat ]
set-default-shape boats "arrow"
let $boat-size 1
;; this is the real "0" in terms of even positioning
let $far-left-edge-xcor min-pxcor - 0.5
let $total-width-of-all-boats ($boat-size * $fleet-count)
let $gap-between-boat-edges (world-width - $total-width-of-all-boats) / ($fleet-count + 1)
let $gap-between-boat-centers $gap-between-boat-edges + $boat-size
let $gap-between-left-edge-and-first-boat-center $gap-between-boat-edges + ($boat-size / 2)
;; I use boat-number, rather than who,
;;so this procedure will work even if there are other turtles
let $boat-number 0 ;; 0 to (#fleet-count - 1)
create-boats $fleet-count
[ let $x 0
if-else ( $center-on-patches? )
[ set $x min-pxcor
+ floor ( $gap-between-left-edge-and-first-boat-center )
+ ceiling ( $boat-number * $gap-between-boat-centers )
]
[ ;; position without regard to patch alignment
set $x $far-left-edge-xcor
+ $gap-between-left-edge-and-first-boat-center
+ $boat-number * $gap-between-boat-centers
]
let $y max-pycor
setxy $x $y
set $boat-number $boat-number + 1
]
ask boats [ apply-boat-properties ]
end
Using a Set of Patches
This is a lot like the previous method, but we create a set of patches, then ask the patches to make the turtles. This is useful for creating a set of turtles on a specific area of the world, like on an edge, or in a specific pattern of patches, or filling an area with a randomly scattered set of turtles.
to make-fleet [ $boat-gap ]
let $locations patches with
[
;; rules to find the patches
pycor = max-pycor ;; top row
and
(pxcor - min-pxcor) mod $boat-gap = 0
]
ask $locations [ sprout 1 [ set breed boats ] ]
ask boats [ apply-boat-properties ]
end
Using A List of Coordinates
If the required coordinates are few, or are can't be calculated, you can put the coordinates in a list. The created turtles can pull the coordinates from the list.
to make-fleet [ $fleet-count ]
;; A list of x y coordinate pairs.
;; The coordinate pairs are also in a list
let $coordinates
[
; x y ;
[ 6 0 ]
[ 12 0 ]
[ 18 0 ]
[ 24 0 ]
]
;; initialize the counter uses as the list index
let $boat-number 0
;; make boats
create-boats $fleet-count
[ ;; get the coordinate pair
let $xy item $boat-number $coordinates
;; get the x and y from the pair
let $x first $xy ;; aka item 0 $xy
let $y last $xy ;; aka item 1 $xy
;; apply the coordinate
setxy $x $y
;; increment the index number
set $boat-number $boat-number + 1
]
ask boats [ apply-boat-properties ]
Note that the above will make errors if $fleet-count is more than 4, because the coordinate list has only 4 items.
You could use FOREACH on the list, and create 1 turtle for each coordinate. This is handy when a large list of coordinates have been read from a file.
to make-fleet [ $coordinates ]
;; assume $coordinates is a list of pairs of coordinates.
;; like [ [ 1 2 ] [ 3 4 ] [ 5 6 ] ]
;; we are going to ask the patch at each of the coordinates
;; to create a turtle. Then we will set up the turtle.
( foreach $coordinates
[ [ $xy ] ->
ask patch first $xy last $xy
[ sprout 1 [ set breed boats ] ]
]
)
ask boats [ apply-boat-properties ]
end
Finally
There are other ways, too, and many other formulas for calculated positions.
I'd need to pick an object in a bag containing 20 elements with attributes c (color) and s (size). Both color and size are numbers (e.g. c= {red = 256, black = 0, ... } = {256, 0, ...}).
As in Python I'd use random.choice in numpy library, I found on the web that the corresponding function in Netlogo is the extension rnd.
Struggling along a possible solution, I did
Edited:
breed[people person]
people-own
[
ball
size
color
bag
]
to setup
create-people 5
[ set color gray
setxy random-xcor random-ycor
]
ask people[
set bag [ ] ; 0 items
]
end
To create the balls:
to create-balls
set color random 300 ; color
set size random-float 5 ; size
let this-ball self
ask one-of people [ ; ask one of people to put the ball created into the bag
set bag fput this-ball bag ; add ball to the bag
]
end
The code below should include the part of drawing:
to draw
ask one-of people [
rnd:weighted-one-of bag [ ] ; I do not know what I'd write in the brackets
]
end
As you can easily see, I've many doubts about how to implement the code.
How can I select one item from the bag depending on its size (or color)?
Can you please help me out with it?
Here is a complete model that creates people and balls as turtle agents and has 30 of the balls get chosen weighted by their size. It then opens an inspect window for the person who has chosen the most balls.
extensions [rnd]
breed [people person]
people-own [ my-balls ]
breed [balls ball]
balls-own [ chosen? ]
to setup
clear-all
create-people 20
[ setxy random-xcor random-ycor
set my-balls (turtle-set nobody)
]
create-balls 50
[ hide-turtle
set size one-of [1 2 3 4 5]
set color one-of [red white blue yellow]
set chosen? false
]
repeat 30 [draw-ball]
inspect max-one-of people [count my-balls]
end
to draw-ball
ask one-of people
[ let bag-of-balls balls with [not chosen?]
let choice rnd:weighted-one-of bag-of-balls [size]
ask choice [set chosen? true]
set my-balls (turtle-set my-balls choice)
]
end
Some things to notice:
There are NO lists in this code. There are situations where you should use lists. Common uses include memory where the order is important (eg you only want to keep track of the last 5 other people seen) or where the same agent can appear multiple times. And the list commands are very powerful. However, unless you need a list then you should use agentsets.
Each person has their own bag called 'my-balls' that contains the balls they select. That is initialised as a turtle-list as part of the setup.
I used a variable called 'chosen?' that is owned by each ball to track whether it is still in the bag for the next person to choose. Then the bag-of-balls is created only as all the balls not yet chosen.
The code for weighted random choice (when choosing from agentsets) simply has the name of the variable holding the weight as the reporter, but you could use some function such as rnd:weighted-one-of bag-of-balls [size ^ 2] if you wanted a more complicated weighting scheme.
my model is a network of agents connected to each other with links.
I try to create a agentset from the neighbors of an agents and their neigbors and so on (I need this to assign different values to it).
However when I create a let with the agentset in it. the agents asked to make this agentset all have their own, this is so far so good. But when I want the original agent to ask him his second line neighbors he just returns an agentset from one of this neighbors instead of the combined agentsets of all his second line neighbors
I want the neighbors to store their own neighbors into a agentset with all the neighbors from the different agents in that set.
I cant ask the let agentset to simple do turtleset current-agentset new-agentset since in a let you cant ask to let variable. So a code which would normally be set second-neighbors (turtle-set second-neighbors other-nieghbors doesnt work since I cant ask second-neighbors already in a let
I also cant make this a global or somethins since it is agent specific.
the code I have so far looks like this
ask companies [
let this-company self
let b link-neighbors
ask b [ let c link-neighbors with [self != this-company]
ask c [ let d link-neighbors with [not member? self b]
ask this-company [
set iburen b
set iiburen c
set iiiburen d
]
]
]
]
so what I want is that all the agents in the agentset c report their link-neighbors like they do now. But also store these link-neighbors into a new agentset which has all the link-neighbors of all the agents in c. like a simple i i + 1. but than with turtle-set (what I have) (what is new from the next agent asked)
the same goes for d
If I run the model now agents report different agentset almost every tick. They just pick one agentset from any of these agents instead of combining them all togother.
Here is what I think you need:
extensions [ nw ]
breed [ companies company ]
companies-own [
buren ; a list of agentsets, with one item for each "level" of neighbors
]
to setup
clear-all
; create a random network and lay it out:
create-companies 20 [ create-links-with n-of 3 other companies ]
repeat 30 [ layout-spring turtles links 0.2 5 1 ]
let num-levels 3
ask companies [
let all-neighbors other nw:turtles-in-radius num-levels
set buren (list) ; initialize to empty list
foreach range num-levels [ i ->
let neighbors-at-this-level all-neighbors with [
nw:distance-to myself = i + 1
]
set buren lput neighbors-at-this-level buren
]
]
; demonstrate how to access the levels (sorted only for display purposes)
ask one-of companies [
show sort item 0 buren ; first level neighbors
show sort item 1 buren ; second level neighbors
show sort item 2 buren ; third level neighbors
]
end
This might not be the most efficient code possible, because it goes through the list of all neighbors once for each level, but unless you have a humongous network, you should not notice.
If you really wanted to use variables like iburen, iiburen and iiiburen, you could always alias the items of the list:
set iburen item 0 buren
set iiburen item 1 buren
set iiiburen item 2 buren
...but I don't recommend it. Having your agentsets in a list should encourage you to think of your levels in a more general way.
I want to get a list of top ten turtles in terms of their degree centrality. I have tried but I am not getting the required result.
In the code below, I am storing centrality in a list and then reverse sorting it. However, it is storing centralities only. I want turtles ordered in terms of their centrality. I also have tried saving turtles on the list and have used sort-by but got an error.
I also have tried to get agents using turtles with max degree centrality, but the problem arises when several nodes have the same centrality. I want to do this in an efficient manner.
globals [indeg]
turtles-own [centrality]
to setup
ca
crt 160
ask turtles [
set indeg []
fd random 15
]
ask turtles with [color = red] [create-links-to other turtles with [color = blue]]
ask turtles with [color = green] [create-links-from other turtles with [color = yellow]]
inf
end
to inf
ask turtles [
set centrality count my-in-links
set indeg lput centrality indeg
]
set indeg sort(indeg)
print "indeg"
print reverse(indeg)
print max(indeg)
end
Here are three different ways to get that information, with potentially slightly different performance and results:
to setup
clear-all
create-turtles 160 [ forward random 15 ]
ask turtles with [color = red] [create-links-to other turtles with [color = blue]]
ask turtles with [color = green] [create-links-from other turtles with [color = yellow]]
let top-10-a reverse sort-on [ count my-in-links ] max-n-of 10 turtles [ count my-in-links ]
show-results top-10-a "Top ten turtles using max-n-of:"
let sorted-turtles reverse sort-on [ count my-in-links ] turtles
let top-10-b sublist sorted-turtles 0 9
show-results top-10-b "Top ten turtles from sorted list:"
let top-10-c filter [ t ->
[ count my-in-links ] of t >= [ count my-in-links ] of item 9 sorted-turtles
] sorted-turtles
show-results top-10-c "Turtles with top ten centrality:"
end
to show-results [ turtle-list title ]
print title
foreach turtle-list [ t -> ask t [ show count my-in-links ] ]
end
The first (method "a") and most obvious is to use NetLogo's max-n-of primitive. That primitive gives back an agentset (not a list), so if you want an agentset, that's the way to go.
Your question seem to indicate that you ultimately want a list of turtles sorted by decreasing centrality, so you have to use reverse sort-on [ count my-in-links ] on the result of max-n-of, which is what I'm doing above.
Another approach (method "b") would be to sort all turtles by their centrality, store the resulting list in sorted-turtles variables and then take the first 10 of that. That method is a bit more intuitive but could be slower than the max-n-of method since it has to sort the whole list. Depending on how many turtles you have, however,the difference could be negligible.
One thing the first two methods have in common is that the ties are broken randomly. This means that if you have, let's say, three turtles that have a centrality worthy of position number ten in your top ten, you'll only get one of those. (Given the way you construct your network in the example from your question, this is very likely to happen.) If you want your top ten to potentially include more than 10 turtles in case of equality, you need to use method "c".
The last method sorts the whole, look at the centrality of the tenth turtle in that list, and filters the list to keep only the turtles with centrality greater or equal to that one.
there is a question that I want to ask that is when I trying to type this code, I got the error that is
The > operator can only be used on two numbers, two strings, or two agents of the same type, but not on a number and a list.
What I want to ask is how can I fix this, the false happen at this line on the code :
if pri-lev > [pri-lev] of oppoint1 and pri-lev > [pri-lev] of oppoint2
I tried to change it into "cars-on" or "cars with" but they are all useless. I also try to find on the Netlogo dictionary but I found no results on the code for directing an agent on a specific path.
What I am trying to do here is when an agent comes to a specific section, it will check if any agents listed as "oppoint1"; "oppoint2"; "oppoint3"; "oppoint4" and then compare a value call pri-lev to others value for setting its decision on keeping on moving or stopping and wait for others.
These are the part of my code:
ask cars
[
let oppoint1 (cars-at (xcor + 2) (ycor + 2))
let oppoint2 (cars-at (xcor - 1) (ycor + 1))
let oppoint3 (cars-at (xcor - 2) (ycor + 1))
let oppoint4 (cars-at (xcor - 3) (ycor + 1))
ifelse oppoint1 != nobody and oppoint2 != nobody
[
if pri-lev > [pri-lev] of oppoint1 and pri-lev > [pri-lev] of oppoint2
[
set pri-lev 4
speed-up
]
]
[
if oppoint2 = nobody and oppoint3 = nobody and oppoint4 = nobody
[
set speed 1
fd speed
if turning = "Rtrue"
[
set heading heading + 90
speed-up
]
]
]
]
Sincerely, Minh
it seems that the reason you are getting this error is that you are comparing the attribute of one (the current car) to the attributes of many (the oppoint agent-sets). Your code now says something like "If my privilege is greater than the privilege of that group, do this thing..." The problem is that [pri-lev] of oppoint1 returns a list of the pri-lev of all members of the oppoint1 agentset, like [ 10 12 13 24 ], and Netlogo won't automatically iterate over that list and compare each item to the attribute of the asking turtle.
There are several ways to deal with this. For example, you could make sure that you only ever compare two turtles- maybe by making sure that you only ever have one turtle per patch at a given time. If you are going to potentially compare one agent to an agent-set, you can use the any? primitive to check if any members of the group you're looking at satisfy your conditional statement. For example, given this setup:
turtles-own [
pri-lev
]
to setup
ca
reset-ticks
crt 10 [
set pri-lev 1 + random 10
]
end
You can ask one-of your turtles to check if not any? of the turtles on the current patch have a higher pri-lev than the asking turtle. If none of them do, the current turtle will move forward. Otherwise, it will print that there is another turtle with a higher pri-lev on the current patch.
to compare-with
ask one-of turtles [
let other-turtles other turtles-here
ifelse not any? other-turtles with [ pri-lev > [pri-lev] of myself ] [
fd 1
]
[
print ("A turtle here has a higher pri-lev than I do." )
]
]
tick
end