in simple words what I am struggling to do is:
if (colour of any patch = red) then execute some code
if any? patches with [pcolor = red] [
print "yes, there is at least one red patch"
]
Only a turtle can check the pcolor. So this works:
ask turtles [show pcolor]
But this does not work (typed in on the Observer> prompt):
show pcolor
Related
I'm new to NetLogo and I have a question that I'm sure is pretty basic. But, I'm not getting over the difficulty.
If anyone can help me overcome this difficulty, I would be very grateful.
I would like from the patch where the turtle is found to consider the 8 neighboring cells in search of the highest pveg value. If it has equally high values, choose 1 of these randomly. Upon finding the highest pveg value of the neighbors, the turtle went there.
I am using the command: max-one-of. I think it serves my purpose. But, I'm making some syntax error that shows the following error: MOVE-TO expected input to be an agent but got NOBODY instead.
Thanks in advance
extensions [ gis ]
globals [ veg ]
patches-own [pveg]
to setup
clear-all
reset-ticks
setup-patches
crt 1 [
ask neighbors [ set pcolor blue ]
set color black
]
end
to setup-patches
end
to go
ask turtles [neighboring]
end
to neighboring
let my-neighWith-pveg [ neighbors with [pveg > 0.2] ]of patch-here
ifelse neighWith-pveg = 0
[ ]
[ move-to max-one-of patches [my-neighWith-pveg] set pcolor red ;;ERROR HERE
]
end
The NetLogo dictionary says, max-one-of needs an agentset and a reporter as input:
max-one-of agentset [reporter]
In your code, you use two agentsets: turtles and my-neighWith-pveg
Since you want to chose from the neighbors (and not all turtles) with the hightes pveg, you can write:
max-one-of my-neighWith-pveg [pveg]
Is it possible to have a turtle move towards a patch with a certain color?
i.e. have a turtle move towards red patch from blue patch?
sure enough
ask the turtles in question to
face one-of patches with [pcolor = red]
fd 1
although you should do some exception handling because if there is not a patch of that color you will get a
"FACE expected input to be an agent but got NOBODY instead. error
while turtle 0 running FACE called by Agent Monitor"
error
I do it something like this
let targ one-of patches with[pcolor = red]
if targ != nobody [set heading towards targ fd 1]
I hope that works for what you want.
Alternately as I was reminded in the comments.
If any? Patches with[ pcolor = red]
[set heading towards one-of patches with[ pcolor = red ] fd 1]
But as Seth says in the comments that computes the red patches twice which is costly.
I want to simulate reproduction process of turtles in time when single patch can by used only once. If the patch is red and ticks mod 50 = 0 then turtles-here (on this patch) hatch new 10 turtles. Every patch can be used only once during the whole simulation run.
Please, how can I include this condition into my code? I tried simple to change patch color to green with hope that the next hatching process will run only with red ones. However next time step NetLogo doesn't keep this patch green but changes it back to red. Thus my reproduction run from the same patch.
Any suggestions will be highly appreciated
The part of my code:
to go
if ticks mod 50 = 0 [ask patches with [pcolor= red] [reproduce] ]
end
to reproduce
ask one-of turtles-here
[hatch 10 ;
die]
; set pcolor green - change infestlev from 2 to 5 only for specific tick, not for the rest of the simulation
end
The code you have should work fine. In your description, you state that the colour turns back to red - so that's why this code isn't working, somewhere else you have a colouring procedure. Alternatively, if you don't want to rely on colour (or if you want colours to mean something else), then you can add a variable to each patch to keep track of whether it has already reproduced.
patches-own [reproduced?]
to setup
...
ask patches [set reproduced? FALSE]
...
end
to go
if ticks mod 50 = 0 [ask patches with [not reproduced?] [reproduce] ]
end
to reproduce
ask one-of turtles-here
[ hatch 10
die ]
set reproduced? TRUE
end
Just as a general comment, it is a little odd to ask the patch to reproduce when what you are really trying to do is have the turtle on a patch reproduce. Logically you are saying that once one turtle on a patch has reproduced, then no other turtle on that patch can ever reproduce. If the reproduction is truly governed by the patch, it would be more usual to use sprout instead of hatch. That gets you code that looks like this:
to reproduce
sprout 10 [ any commands you want the new turtles to do ]
set reproduced? TRUE
end
My final working code with steps (available here: http://ulozto.cz/xRqtDDfV/timing-of-turtle-sprout-nlogo):
setup turtles
if turtle touch red patch, turn this patch blue
at the same time - tick 10 -> sprout from every blue patch 10 nwe turtles
every patch can be used only once during simulation run (turn red, assured by reproduced? variable)
enter code here
patches-own [reproduced?]
to setup
clear-all
setup-turtles
setup-patches
change-color
reset-ticks
end
to setup-patches
ask patches [set reproduced? FALSE]
ask patches [set pcolor green]
ask n-of 80 patches [set pcolor red] ; identify turles which could be a source for new turtles
end
to setup-turtles
crt 1
ask turtles [set color yellow]
end
to go
if ticks mod 10 = 0 [
ask patches with [(pcolor = blue) and not (reproduced?)]
[reproduce] ; set reproduction to every 10 ticks for all blue patches
]
move-turtles
change-color
tick
end
to move-turtles
ask turtles [fd 1]
end
to change-color ; if turtle touch red patch, red turns blue
ask turtles [if pcolor = red
[set pcolor blue]
]
end
to reproduce ; sprout 10 new turtles from blue patches at defined time step (multiply of 10 ticks)
sprout 10
set reproduced? TRUE
end
How can I delete patches that have a specific color ("clear-patches" deletes all patches? For example, from this code, I would like to delete all blue patches and keep only yellow patches.
to test
clear-all
ask patches [ set pcolor yellow]
repeat 20 [
ask one-of patches with [pcolor = yellow] [ set pcolor blue]
]
end
Thank you very much for your help.
Not exactly sure what you what "deleting" a patch to mean. Unlike turtles and links, patches cannot be killed.
If by "delete a patch" you mean "reset all of the patch's variables to their defaults", there isn't any command in NetLogo that does that to only some patches, instead of all them.
If you just want to clear certain variables in certain patches, you have to name those variables explicitly, for example:
ask patches with [pcolor = blue] [
set pcolor black
set plabel ""
...
]
I am trying to make my turtle change the color of a patch when it comes into contact with it and have tried the following code:
to deesculateviolence
ask turtles [
if pcolor = red [set pcolor blue]
]
end
The code does not come up with any errors but when I play the model, the color of the patch does not change. I have tried similar codes from different models and still cannot get the patch to change color. If anyone knows where I am going wrong I'd really appreciate your help.
I think your code does the right thing :
to setup
clear-all
create-turtles 5 [
move-to patch random 20 random 20
]
ask n-of 25 patches [set pcolor red]
reset-ticks
end
to go
ask turtles [
rt random 10
fd 1
if pcolor = red [set pcolor blue]
]
tick
end
you can see the effect in following example better