NetLogo: select a patch with neighbors having certain qualities? - distance

I want to let my turtle move to certain patch and make a "splotch". The central patch = my turtle location, can be selected randomly, however satisfy two conditions:
has to be in a certain distance from turtle's actual position
has to surrounded (neighbors in certain radius) by patches with specific quality
The reason is to create kind of "buffers" around my turtle's position, with aim to obstruct the close proximity of my clumps.
Please, how can I satisfy these two conditions?
As far, I have:
to go
ask turtles [
; select one of patches in specific distance, and
; surrounded by patches with no magenta color
let aaa one-of patches with [distance myself > 3 and
all? neighbors with [pcolor != magenta]]
; how to write this condition above ??
; and how replace "neighbors" by "in-radius"??
move-to aaa
ask neighbors [ ; create clump of magenta patches
set pcolor magenta ]
ask patch-here [ ; set central patch to magenta
set pcolor magenta ]
]

You're almost there; you just need to reread the documentation for all? and any?.
let _candidates patches with [distance myself > 3]
set _candidates _candidates with [
not any? (patches in-radius 3 with [pcolor = magenta])
]
let aaa one-of _candidates
If it is possible that there will be no candidates, you should guard against that.

Related

netlogo: have patches calculate influence value using reporter

I'm modeling a cityscape for looking at movement, where patches equate to buildings and have different influence values. I need to use a reporter function that calculates the value of each patch with something like:
(its own influence) plus (the influence of neighbors) divided by the
distance to a specific turtle (max-one-of distance myself)
The turtle will then move towards the patch with the highest influence value, but along a defined street.
I'm new to using netlogo and have gotten completely stuck.
I've included a portion of what I have so far, but I can't figure out how to write the reporter function that will compute each patches influence value (in-cone) so that the turtles can then move towards the best option.
to setup-influence-field
ask patches with [pcolor = green] [set influence commercial-influence]
ask patches with [pcolor = orange] [set influence production-influence]
ask patches with [pcolor = yellow] [set influence domestic-influence]
ask patches with [pcolor = pink] [set influence religious-influence]
ask patches with [pcolor = blue] [set influence public-influence]
end
to go
move-serapis
end
to move-serapis
ask serapis [set-procession-heading]
repeat 2 [ ask serapis [ fd .25 ] display ]
tick
end
;;;;; the reporter values are need for this part of the code so that the turtles (serapis) can move towards the patches with the highest influence value;;;;
to set-procession-heading
let direction patches in-cone 4 40 with [influence-field > 0]
if any? influence-field
[face max-one-of influence-field] ;;;; face towards the highest computed influence value
ifelse any? patches with [pcolor = black] in-cone 1 25
[process]
end
Any help would be greatly appreciated!
I don't think this is completely correct and I can't test it, but it should start you off and maybe someone here can fix it if you let us know the errors.
to set-procession-heading
let direction-targets patches in-cone 4 40 with [influence-field > 0]
if any? direction-targets
[ face max-one-of direction-targets [ influence-amount self ] ]
end
to-report influence-amount [ target-node ]
report ( [ influence-field ] + sum [ influence-field] of neighbors ) / distance target-node
end
What I have done is set up a separate procedure to report the results of your calculation. That procedure takes an argument (named target-node) because you need to be able to pass the identity of the turtle being influenced. Once you have that procedure, then you can simply pass the agent-set of potential directions to the calculation procedure and pick the one with the largest value.

NetLogo: identification of valleys = rivers location in artificial landscape

I want to produce the artificial landscape, containing hills, slopes and valleys. So far, so good. Now, I want to place a rivers in the bottom of the valley. I thought that the easiest way will be ask turtle to move uphill/downhill by elevation as drops here: http://modelingcommons.org/browse/one_model/2352#model_tabs_browse_info
However, as my landscape is not real, my valleys are also not linears, but just the "depressions" in the terrain, and thus my river localisation is really weird looking?
Please, is there a way to create hills and valleys reflecting the real terrain in netlogo without using GIS extension? I've found great models of Erosion, Watershed and GIS gradient example, but how can I initially place my turtles to stay only in valleys?
EDIT
the GIS gradient example provide excellent problem solving of movement of all the cells over the space, and they aggregate in valleys. However, as I want to by movement of my turtle "create" the river bed on the bottom of the valley, how can I place it? maybe start at the lowest point and stop after several ticks to not to allow to get on the top of the hill? thank you !
globals [
low
high
range ]
patches-own [
altitude ]
to setup
clear-all
setup-hills
scale-patches
color-patches
end
to setup-hills
ask n-of 2 patches [
set pcolor magenta ]
ask patches [
let max_dist sqrt (world-width ^ world-width + world-height ^ world-height)
set altitude world-width - distance patch 10 10
set altitude world-width - distance min-one-of patches with [pcolor = magenta][distance myself]
]
crt 1 [ ; create a turtle, needed to identify the lowest slope
set color red
let bottom_valley min-one-of patches [altitude]
move-to bottom_valley
]
end
to scale-patches
set low [altitude] of min-one-of patches [altitude]
set high [altitude] of max-one-of patches [altitude]
set range high - low
ask patches [
set altitude altitude - low ; shift every patch down so lowest altitude is 0
set altitude altitude * 99.0 / range ; scale every patch so that the lowest is 0 and highest is 999
]
repeat 5 [
diffuse altitude 0.5 ]
end
to color-patches
ask patches [
set pcolor scale-color green altitude 0 100]
end
to create-river
ask turtles [
let p max-one-of neighbors in-radius 1 [altitude]
if [altitude] of p >= altitude [
face p
move-to p
set pcolor blue
]
]
end
You have the right general idea. I recommend checking out the "GIS Gradient" model on your landscape. You can find it in the Models Library under Code Examples/GIS. Then think how to filter patches that have a minimum number of water particles passing through it over time.
Identification of system of rivers on the landscape using GIS Gradient Example:
http://modelingcommons.org/browse/one_model/2352#model_tabs_browse_info
The whole process of identification of the river system on the complex landscape is composed by 3 subprocesses:
identify the highest points of the landscape
place here the river source (create-source)
identify patches for a downhill stream
from the highest river source, by decreasing elevetion of neighboring cells to the lowest elevation of the river valley
when turtle reaches the edge of the world, turtle dies (go-downhill)
remove top hill points (as the river does not read the summit of the hill)
the river does not start at the top of the hill, but at the highest point of the valley
the highest "river" patches from the river beds system are removed (remove-river-from-top-hill)
The number of sources depends of type of GIS data you have available. The same for the number of patches you wish to remove from the top of the hill.
;; ----------------------------------------------
;; create river
;; ----------------------------------------------
to create-source
; identify the 5 highest points of the landscape
repeat 5 [
; avoid the highest points to be close to each other
ask max-one-of patches with [ not any? turtles-here and not any? turtles in-radius 20 ] [p_elev] [
;ask patches to sporout turtles
sprout 1 [
set size 1
set color orange
]
]
]
end
to go-downhill
; stop if there is no more turtles
if not any? turtles with [color = orange]
[ stop ]
; ask turtles located on top of thehills to move downhill
ask turtles with [color = orange] [
; die when you reach the edge of the world
if ([pxcor] of patch-here = max-pxcor) or ([pycor] of patch-here = max-pycor)
or ([pxcor] of patch-here = min-pxcor) or ([pycor] of patch-here = min-pycor) [
die ]
move-to patch-here ; go to patch center
set pcolor blue ; identify the use of patch
set p min-one-of neighbors with [pcolor != blue ] [p_elev] ;; or neighbors4 with [pcolor != blue]patches in-radius 3
if p != nobody [
; move downhill if elevation of patch you are standing on is higher then one of the neighboring patches
ifelse [p_elev] of p <= p_elev
[
face p
move-to p
set pcolor blue ; identify the use of patch
]
[
;move-to min-one-of patches with [pcolor != blue] [distance myself]
move-to min-one-of patches in-radius 2 with [pcolor != blue] [p_elev]
set pcolor blue ; identify the use of patch
]
]
]
end
to remove-river-from-top-hill
; remove 5% of the blue (river) patches placed on the top of the hill
let total_blue count patches with [pcolor = blue]
repeat total_blue * 0.05 [
ask max-one-of patches with [pcolor = blue] [p_elev] [
set pcolor yellow ]
]
end
Complex river system identified:
(river bed = BLUE, removed top of the hill = YELLOW):

How to ask turtles to place in a desired area, on Netlogo?

I want to create turtles, which they place in a desired area with random coordinate:
they should place in the white area and in middle of it in a line. in other words, in the top regtangle, their xcor should be random and their ycor is 10. in the right regtangle, their ycor should be random and their xcor is 10 and so on.
When you create turtles, you can give them instructions such as their location. For example:
create-turtles 1 [ set ycor 10 ]
Alternatively, you can sprout the turtles from the relevant patches and their location will already be set. For example:
ask n-of 5 patches with [pcolor > 1] [ sprout 1 ]
to place-on-color [#color]
let _patches (patches with [pcolor = #color])
ask turtles [
move-to one-of (_patches with [not any? turtles-here])
]
end
Add error checking if you may have too many turtles. (Or remove the unique occupancy constraint if you don't want it.)

How to detect neighbors patches coordinator (position)?

How to detect coordinators (positions) of neighbors patches which surrounding the patch that a turtle is on? Something like:
patches with [(pcolor = red) and (any? turtles-on neighbors)]
or
[patch-here] of neighbors with [(pcolor = red)]
I would want to move the turtle to a neighbor patch with red color. So I will need to find that neighbor patch with red color first. Thanks.
one-of may do what you want here (http://ccl.northwestern.edu/netlogo/docs/dictionary.html#one-of). Something like this:
to move-turtle
let destination one-of neighbors with [ pcolor = red ]
if (destination != NOBODY) [
move-to destination
]
end
It is a bit difficult to figure out what you want, but I think you are suggesting to work with coordinates rather than with patches. If so, don't do that unless there is a good reason. In this case you can just
to move ;; turtle proc
let %candidates neighbors with [pcolor = red]
if (any? %candidates) [
move-to one-of %candidates
]
end

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.