NetLogo : make certain turtles not move at all or stop moving - netlogo

I want certain turtles in NetLogo to just not move at all AND I want other certain turtles to stop moving.
I have created 5 black turtles which I do not want to move at all and I tried something like
ask turtles with [color = black] [fd 0] but that won't work, they still move like the green turtles, which currently is fd 1.
I also need n-of green turtles to stop moving in the middle of the simulation and I have NO idea how to do that. The n-of could also be replaced with a slider.
Thanks!

In the part of your code where you have:
ask turtles [ fd 1 ]
change it to
ask turtles with [color != black] [ fd 1 ]
As for "I also need n-of green turtles to stop moving in the middle of the simulation", consider an approach such as:
turtles-own [velocity]
to setup
...
;; make some green turtles that move
create-turtles 10 [ set color green set velocity 1 ]
;; make some black turtles that don't move
create-turtles 10 [ set color black set velocity 0 ]
...
reset-ticks
end
to go
...
;; make some green turtles stop moving
ask n-of 5 turtles with [color = green] [
set velocity 0
]
...
ask turtles [ fd velocity ]
...
tick
end
Make sense?

Related

How to spawn turtles a certain amount of patches away from each other

I am trying to spawn turtles 5 patches away from each other but I'm not sure how, right now they all spawn on green patches (I don't want them to spawn on brown ones) and I'm not sure how exactly you control the distance between the spawning of turtles, thanks.
breed [ humans person ]
breed [ zombies zombie ]
to setup_world
clear-all
reset-ticks
ask patches [
set pcolor green
]
ask n-of 100 patches [
set pcolor brown
]
ask n-of 15 patches with [pcolor != brown][sprout-humans 1 [set size 5
set color blue
set shape "person"]]
ask n-of 5 patches with [pcolor != brown][sprout-zombies 1 [set size 4
set color red
set shape "person"]]
end
Have you read this question: NetLogo Create turtle at regular distance from each other?
Anyway, I thought that showing you some working functions would be helpful, here I made two alternatives, sprout-distanced1 and sprout-distanced2, you can test them both by alternating which line is commented; I also added a slider called Min-Distance to control the turtles spacing.
sprout-distanced1 uses the keyword carefully with is basically a try-else block, it's there in case that the turtle doesn't find a patch distanced enough to move to, in which case rather than sending a warning the turtle will stay where it is and print its distance to the closest turtle.
sprout-distanced2 uses a while loop, in case that the turtle doesn't find a place to move to that is at least Min-Distance from another turtle it will reduce the minimum radius by a small amount until it can distance itself from other turtles, if it had to move to a patch where it is less than Min-Distance away from other turtles it will log the distance at the Command Center.
breed [ humans person ]
breed [ zombies zombie ]
to setup_world
clear-all
reset-ticks
ask patches
[
set pcolor green
]
ask n-of 100 patches
[
set pcolor brown
]
ask n-of 15 patches with [pcolor != brown]
[
sprout-humans 1
[
set size 5
set color blue
set shape "person"
;sprout-distanced1
sprout-distanced2
]
]
ask n-of 5 patches with [pcolor != brown]
[
sprout-zombies 1
[
set size 4
set color red
set shape "person"
;sprout-distanced1
sprout-distanced2
]
]
end
to sprout-distanced1
carefully
[
; try to move at least Min-Distance away from other turtles
move-to one-of patches with [not any? other turtles in-radius Min-Distance]
]
[
; if can't move Min-Distance away from other turtles
; stay put and log the min distance to other turtle, just for reference
show distance min-one-of other turtles [distance myself]
setxy random-xcor random-ycor
sprout-distanced1
]
end
to sprout-distanced2
let min-dist Min-Distance
let moved? FALSE
while [not moved? and min-dist > 0]
[
; can distance it self somewhere?
ifelse any? patches with [not any? other turtles in-radius min-dist]
[
; if yes, go there
move-to one-of patches with [not any? other turtles in-radius min-dist]
set moved? TRUE
; if had to reduce the distancing radious log it
if moved? and min-dist < Min-Distance
[
show distance min-one-of other turtles [distance myself]
]
]
[
; no where to go, reduce the distancing radious
set min-dist min-dist - 0.1
]
]
end
Choose whichever suits better your model.

How to stop NetLogo simulation

I am trying to create a simulation of Covid19 spread for months: May and June
The code I am using to create turtles and start simulation is showed below:
to gh-month
if month="May"//month is a chooser in interface tabe
[
clear-all
create-turtles 3000
[
setxy random-xcor random-ycor
set shape forma
set color blue
]
set no_infected 106
ask n-of 1 turtles with [color = blue]
[
set infectedTurtle? True
set color red
]
set percentage(no_infected / 3000)* 100
]
if month="June"
[
clear-all
create-turtles 3000
[
setxy random-xcor random-ycor
set shape forma
set color blue
]
set no_infected 2030
ask n-of 1 turtles with [color = blue]
[
set infectedTurtle? True
set color red
]
set percentage(no_infected / 3000)* 100
]
end
And setup and go commands are below
to setup
gh-month
end
to go
reset-ticks ;; netlogo time
ask turtles [
forward 0.005 ;; moving turtles command and speed
]
ask turtles with [color = red] [
ask other turtles-here [
if random 100 < percentage[set color red]
]
]
set %infected (count turtles with [color = red] / count turtles) * 100
if %infected= percentage[stop]//percentage is declared above also is a monitor in interface tab
end
My question after simulation start, why for the month' May' is stopped ate based on given condition(if %infected= percentage[stop]), and for June no, it goes up to 100% and don't stop at given condtion.
Thanks to everyone
You have a basic misunderstanding of how time operates in NetLogo so there are several problems. You have also written way too much code at once. For example, just create the turtles and get that working before having them move, and get that working before trying to have different months.
NetLogo works with a counter or clock. Each tick increments the counter. The reset-ticks is part of the initialisation because it sets the counter to 0 and makes it available. The command tick advances the clock, and is usually the last command in the procedure that contains all the things that happen in a day (or hour or whatever a tick represents). The go procedure therefore needs the command tick, not the command reset-ticks.

set a demand and supply curve for the model tragedy of the commons in the case of an overfished pond

I am new at net logo and I want to write a model based on tragedy of the commons in the case of an overfished pond. The purpose is to find an equilibrium between fishers and fishes based on an economic model with demand and supply. If there are less fishers, more fishes will be in the pond, then after a certain time (ticks) the number of fishers increases and less fishes will be in the pond. Maybe set like a number of fishes per day that can be fished. Thus, the solution is to find a convenient number of fishers as the fishes can still reproduce. I want to have a box in the interface where I can type in a number and see what happens with the number of fishes.
I have no idea how to set this up. I hope to hear from you :)
I started with this code:
breed [fishers fisher]
breed [fishes fish]
to setup
clear-all
reset-ticks
ask patches [set pcolor blue ] ;; lake/pond in form of a rectangle in color
ask patches [ if pxcor > 8 [ set pcolor green ]]
ask patches [ if pycor > 8 [ set pcolor green ]]
ask patches [ if pycor < -8 [ set pcolor green ]]
ask patches [ if pxcor < -8 [ set pcolor green ]]
ask one-of patches with [ pcolor = blue ] [ sprout 20 [set shape "fish" set color pink set size 1.5 ]] ;; creates fishes
ask one-of patches with [ pcolor = green ] [ sprout 2 [set shape "person" set color black set size 3 ] ] ;; creates fishers
end
to go
tick
;;fishes
ask turtles with [ shape = "fish" and color = pink ]
[ right random 360 forward 1
if [pcolor] of patch-ahead 1 = green [ right 180 fd 1 ]]
;; fishers
ask turtles with [ shape = "person" and color = black]
[;right random 360 forward 1
if any? patches with [pcolor = blue]
[set heading towards one-of patches with [pcolor = blue] forward 1]
if [pcolor] of patch-ahead 1 = blue [ right 180 fd 2 ]]
ask turtles with [shape = "person" and color = black]
[if any? turtles with [shape = "fish" and color = pink] in-radius 2
[ask turtles with [shape = "fish" and color = pink] in-radius 2 [die]]]
end
Firstly, I suggest you look through existing models in the Netlogo library (Wolf-sheep-predation model may help). You roughly have the right idea in your current code, but you should look at other models to improve. You've already set your different breeds of turtles, but you should also set up their respective shapes under 'setup'. This would help you a great deal later - instead of calling for
ask turtles with [ shape = "fish"...]
you can simply
ask fishes [do sth...]
For that 'box at the interface', you can have a slider at the interface determining the number of fishers you want your run to start with. With another slider, you can set the fishing pressure in your simulated run (i.e. how many fish each fisher will catch) and I suppose you can also consider how this changes when population of fish decreases.
Finally, for a model like yours, you can observe the supply and demand trend by plotting the curves of no. of fishers over time and no. of fishes over time. Again, look at the wolf-sheep-predation model to have an idea of how to do this.
I can't give you more than this I'm afraid since I'm no pro myself but hope this helps a little. Hope someone else would be able to give you a clearer idea.

How to make simulation run faster in netlogo instead of using Slider bar near to view update

Is there any code to make simulation run faster in netlogo, instead of using slider bar near to setting? What my code need to do is to simulate the crowd behavior, it's work fine if the number of turtles around 100,however when I increase the number up to 300-800 turtles, simulation take very long to finish. Each tick also take very long to count from 0 to 1 and next until all turtles die. one thing that I suspect cause slow simulation is when ask turtles to evacuate. without evacuate rule, everything went smoothly even set a maximum number of turtles. is there other way to write evacuate rule, so that it can run faster? thanks.
to go
ask turtles [wander fd 0.01]
if emergency? = true [move]
if all? turtles [ pcolor = red ] ;stops simuation
[stop]
tick
end
to wander
[ do..something]
end
to move
set time-to-evacuate time-to-evacuate + 1
ask turtles [avoid-obstacles fd 0.1]
ask turtles [follow-leader fd 0.1]
ask turtles [flock fd 0.1]
ask turtles with [pcolor != red] [evacuate fd 0.1]
ask turtles with [pcolor = red][die]
end
to evacuate
ask turtles with [color = black ]
[let beings-seen patches in-cone 10 135 with [pcolor = red]
if any? beings-seen
[ let target one-of beings-seen
face target]]
ask turtles with [color = white ]
[let beings-seen patches in-cone 5 135 with [pcolor = red]
if any? beings-seen
[ let target one-of beings-seen
face target]]
end
to avoid-obstacles
[do something]
end
to follow-leader
[do something]
end
to flock
[do something]
end
In your move procedure you have:
ask turtles with [pcolor != red] [ evacuate ... ]
And then in evacuate you have:
ask turtles with [color = black] [ ... ]
evacuate is already being run by all of the non-red turtles, so you've got every non-red turtle asking every black turtle to do something at every time tick.
I don't think you intended that.
I have to guess a bit at your intent, but I think if in evacuate you replace the ask with an if:
if color = black [ ... ]
that's probably closer to what you meant.

On netlogo, what command do I use to make a turtle stop if the patch it wants to move to is a certain color

I'm making a maze on netlogo and I want to do it so that once it tries to walk into the violet lines, it'll stay on its own patch instead of moving forward. What command would that be? I tried bk 1 to reverse the fd 1 but it doesn't work all the time
You can undo your step like this:
ask turtles [
fd 1
if pcolor = violet [fd -1]
]
Or you can check ahead of time as Marzy answered. Basically it's the difference of asking for forgiveness vs permission :-)
I hope this example answer your questions:
turtles-own [target]
to setup
clear-all
reset-ticks
ask n-of 100 patches [
set pcolor red
]
create-turtles 1
[ move-to one-of patches with [pcolor != red]
set heading 90
set target one-of patches with [pcolor != red]
ask target
[
set pcolor green
]
]
end
to go
ask turtles
[ifelse pcolor != green
[
ifelse [pcolor] of patch-ahead 1 != red
[
Your-Move-Function
]
[
Your-Bounce-Function
]
leave-a-trail
]
[stop
print ticks
]
]
tick
end
to Your-Move-Function
let t target
face min-one-of all-possible-moves [distance t]
fd 1
end
to Your-Bounce-Function
let t target
face min-one-of all-possible-moves [distance t]
end
to-report all-possible-moves
report patches in-radius 1 with [pcolor != red and distance myself <= 1 and distance myself > 0 and plabel = "" ]
end
to leave-a-trail
ask patch-here [set plabel ticks]
end
This is how it works:
Random patches are colored Red to show walls or obstacles, one turtle is created in a random location with a random target which is colored green:
I have used a variable to store all available patches which turtle can step on , but since I have considered a target for the turtle, turtle chooses the one patch which is closest to the target, and since I have noticed in some cases it might go in circle I have asked the turtle to leave tick number which is its move number as a plabel, you can use a variable for that for specifying if that path was already selected or not.