How to add 'priorities' to the primite 'n-of' in NetLogo? - list

I have patches with 3 colors (yellow, green, and red). The green ones have a 'rank' value. I would like to ask a given number ('n-cells') of either yellow or green patches ('candidate-cells') to turn red. I am aware I can do that randomly using the primitive 'n-of', like this:
let candidate-cells ( patches with [ pcolor = yellow or pcolor = green ] )
ask n-of n-cells candidate-cells [ set pcolor red ]
But I would like add priorities to the patches that will be turned red. First, I would like yellow patches to turn red (randomly) but if there are still patches to be turned red after all patches yellow have, I would like green patches with highest 'rank' value to turn red until the number of turned patches reaches the 'n-cells' number. I think this piece of code should work till up its last line:
let candidate-yellow-cells ( pcolor = yellow )
let candidate-green-cells ( pcolor = green )
ask n-of n-cells candidate-yellow-cells [ set pcolor red ]
if n-cells > candidate-yellow-cells [
let left-cells ( n-cells - candidate-yellow-cells )
ask n-of left-cells candidate-green-cells [ set pcolor red ]
But still, I am using 'n-of' again for the green cells, I wonder how could I replace that by something that would pick the 'left-cells' as the green patches with highest 'rank' value. Thank you in advance.

This example should get you there:
globals [n-cells]
patches-own [rank]
to setup
set n-cells 500
ask patches [
set pcolor one-of [yellow green red]
set rank random 3
]
end
to recolor
let _yellows (patches with [pcolor = yellow])
let _ny count _yellows
ifelse (n-cells > _ny) [
ask _yellows [set pcolor red]
let _greens sort-on [(- rank)] (patches with [pcolor = green])
let _ng length _greens
let _n min (list (n-cells - _ny) _ng)
ask patch-set sublist _greens 0 _n [set pcolor red]
][
ask n-of n-cells _yellows [
set pcolor red
]
]
end

Related

Netlogo Lists: detecting the patch in a list with max distance to one specific patch - for each turtle

I want to solve a problem in Netlogo that so far exceeds my programming skills. I want to built a list for each turtle which contains the furthest patch the turtle went on this "day". So far I tried to built a list were all patches are stored for each turtle. Now I want to calculate - for each turtle - the patch from this list that has maximum distance from its home (hide). I want to empty the list every night (thats not mandatory) Thats my code so far:
let temp-visited-patch-list lput patch-here temp-visited-patch-list
if period = night
[
[foreach [temp-visited-patch-list] [x -> set visited-patch-list lput (max x [distance hide]) visited-patch-list]]
let temp-visited-patch-list []
]
So I am not that far to extract the values for each turtle seperatly - and even the part I posted does not work. I get an "expected command" error. I would be very thankful for any suggestions to solve this problem.
Best regards
Olivia
This code has the turtles move, remember their furthest patch and turns those patches red and calculates average distance. It should help orient you how to use patches and turtle attributes to solve your question.
globals [home-patch]
turtles-own
[ farpatch
maxdistance
]
to setup
clear-all
set home-patch one-of patches
ask home-patch
[ set pcolor blue
sprout 20
]
reset-ticks
end
to go
repeat 20 [movement]
ask (patch-set [farpatch] of turtles) [set pcolor red]
type "Average max distance:" print mean [maxdistance] of turtles
tick
end
to movement
ask turtles
[ set heading random 360
forward 1
if distance home-patch > maxdistance
[ set maxdistance distance home-patch
set farpatch patch-here
]
]
end

Chemotaxis in NetLogo

I have made a gradient, and I am quite unsure as to how I can make my turtle(s) attracted to one end and also behave a different way. For instance, from light blue to dark blue. Dark blue would be where the food is (chemoattractant), and in this zone, the bacterias would prefer to run randomly or be more energetic. While, in the light blue area, there would be fewer turtles and their movements would be slow or "tumbling."
Overall, how do I make the turtles sense the chemoattractant or the gradient in the patch?
If pcolors were floating point you could just search the immediate neighbors and use
ask turtles [ uphill pcolor ]
but that won't work if the gradient is subtle. The turtles might just sit there.
If you store a floating-point patch variable "exact_color" , say, the next code will work but the angle of motion is always some multiple of 45 degrees.
ask turtles [ uphill exact_color]
So if you generalize the search to a larger radius to determine the local gradient,
this would work:
let neighborhood patches with [ distance myself <= search_radius]
let p max-one-of neighborhood [exact_color]
if [exact_color] of p > exact_color [ face p move-to p]
Here's a working implementation that assigns the color gradient then tracks it.
globals [ scentXC scentYC search_radius ] ;; location of center of maximum scent
patches-own [ exact_color ];
to setup
clear-all
print ("This assumes the world does not wrap");
;; decide to put center of attraction at ( 14, 7 )
set scentXC 14;
set scentYC 7;
;; search a larger radius for gradient since it may be low
set search_radius 5;
color_code_patches
;; next line can visually check work so far
;; ask N-of 20 patches [ set plabel pcolor]
create-turtles 10 [ setxy random-pxcor random-pycor set size 2 set shape "arrow" pen-down];
reset-ticks
end
to go
;; ask turtles [ uphill pcolor ] ;; fails because the gradient is too low
;; following works but the angle of motion is always a multiple of 45 degrees
;; ask turtles [ pen-down uphill exact_color] ;; move one step uphill
;; the following searches a larger neighborhood for the uphill direction
ask turtles
[
;; set search_radius 1.45 to simply search neighbors, ie "uphill exact_color"
let neighborhood patches with [ distance myself <= search_radius]
let p max-one-of neighborhood [exact_color] ;; or neighbors4
if [exact_color] of p > exact_color [ face p move-to p]
]
end
to color_code_patches
no-display
ask patches [
let blueness 0 ;; initialize to make the interpreter happy
let dist distancexy scentXC scentYC
ifelse (dist <= 1) [ set blueness 250 ]
[ set blueness (250 / dist ) ]
set exact_color blueness;
set blueness round blueness;
;;set pcolor [ 0 0 blueness] ;; for unknown reason this doesn't work so more complex
let color_assign ( word "set pcolor [ 0 0 " blueness " ] ")
run color_assign
]
display
end

Netlogo: How can I add some conditions by using the with, if statement or else?

I would like to count the number of turtles stopped on the road, and I want to take that X coordinate information and let it be the queue length. The following is the sample program.
ask turtles with [ not right-end ] ;a flag "right-end" to the red turtle for differentiation to the other blue turtles
[
ask turtles with [ speed = 0 ] ;the speed is 0 means stopped
[
set top max-one-of turtles [who] ;get a turtle with biggest id
set topx [xcor] of top
set L count turtles with [xcor > topx] ; L is the queue length of Little's Law
]
]
I am having trouble understanding exactly what you want to do, but I think it is something like this:
to-report countRightmost ;global context
let ts (turtles with [speed = 0 and not right-end] )
let top max-one-of turtles [who]
let topx [xcor] of top
report count ts with [xcor > topx]
end

Error using "n-of" in NetLogo to select specific patches

I am new to NetLogo and I am working on a deforestation model, where farmers are my agents. They have a ID variable (lotid-farmer) that matches a ID in the patches (lotid-patch) that they own. Basically, farmers check how much money and labor they have to deforest some forest patches or abandon some of their agricultural patches (pcolor = red) in their farms. By the end of the latter procedure, farmers have a "n-aband" value calculated, which is the number of patched they will abandon (randomly) within their farms (pcolor = yellow). This is the piece of code that was supposed to do that:
ask farmers [
...
if pcolor = red and lotid-patch = [ lotid-farmer ] of self [ ; Asks the farmer to randomly convert a # of the agricultural patches without maintenance to regrowth...
ask n-of n-aband patches [ set pcolor yellow ] ; ... among all agricultural patches own by the farmer
]
...
However, when I run the code, farmers start "abandoning" patches that they do not own. I think that is because I am not setting up a proper "restriction" when I use "ask n-of n-aband patches" but I thought that that should be implicit in the "if" statement I have in the line above, no? I have also tried:
ask n-of n-aband patches with [ pcolor = red and lotid-patch = [ lotid-farmer ] of self ] [ set pcolor yellow ]
But I run into a error:
A patch can't access a turtle variable without specifying which turtle.
error while patch 390 414 running OF
called by procedure CALCULATE-DEFORESTATION
called by procedure GO
called by Button 'Go'
Any suggestions on how to get this piece working? Thank you in advance.
To do this, you need to consider only patches owned by the farmer.
ask farmers [
let _id lotid-farmer
let _candidates (patches with [lotid-patch = _id and pcolor = red])
let _n-aband min (list n-aband count _candidates)
ask n-of _n-aband _candidates [set pcolor yellow]
]
But ... don't work with ids. Work with agents. Let each patch have an owner,
which is a farmer or nobody. Let each farmer maintain a list (or agentset)
of patches that it owns.

Netlogo : inequality doesn't work properly under foreach

It supposes to be a simple code, but I don't know why it doesn't work properly.
I want to change a color of non-white turtle back into white if a condition is fulfilled. I put inequality as the condition.
for example, if the amount of red turtle > = 5, then [ do something ].
No error message for the code, but I found that [ do something ] codes are executed before the condition is fulfilled. For example, it is executed when the amount of turtle is 1 or 4. And I also found that there are moments when it reach > = 5, [ do something] code is not executed.
Below is the code
to seize-value
ask consumers [set type-of-value ( list blue red green) ]
foreach type-of-value [
if count consumers with [color = ?] > = 5 [
let z consumers with [color = ?]
ask z [ set color white ]
ask consumers with [color = white] [set value? false]
ask one-of cocreation-patches [ sprout 1 [gen-prevalue]]
]]
end
I've tried using a single color, instead of a list of color (without - foreach) it doesn't work either.
Can anyone help with this?
Thank you
You have something like the following at the top of your code to set up type-of-value as an agent variable:
breed [ consumers consumer ]
consumers-own [ type-of-value ]
However, you are treating it as a global variable in your code. First you say ask consumers [set type-of-value ( list blue red green) ] to set the AGENT variable called type-of-value to the list of colours. But you end that ask [] statement before starting the foreach.
Unless the consumers have different lists of colours, what you really want is something more like this (untested). Note that I have also removed your multiple creations of the same agentset (for efficiency):
globals [ type-of-value ]
to setup
clear-all
...
set type-of-value ( list blue red green)
...
reset-ticks
end
to seize-value
*type "seize-value on tick " print ticks
foreach type-of-value
[ let changers consumers with [color = ?]
*print ?
*print count changers
if count changers >= 5
[ ask changers
[ set color white
set value? false
]
ask one-of cocreation-patches [ sprout 1 [gen-prevalue] ]
]
]
end
UPDATE for debugging I have added three lines that will output key information for debugging. They are marked with an asterisk (*). Add those lines (without the *) and look at the output.