When running two exact same procedures for specific patches, one of the two is stating an error because "it cannot be run in observer context, it is a patches/turtles context only".
to start
ask patches with [seed = 1 AND age = retirement-age] [retirement]
ask patches with [seed = 1 AND age = death] [successor]
end
The retirement-age is an input from the interface.
The death is a patch property, I tried the startprocedure as well with an input from the interface.
The retirement and death procedure are just a copy-paste of each other, using lists created in other procedures. Only the result is different, see below :
to retirement
;;; other calculations same as successor procedure
ifelse (successor-result = 1) [set age 35 ] [set over-retirement 1]
end
to successor
;;; other calculations same as retirement procedure
ifelse (successor-result = 1) [set age 18] [dispatch-parcels]
end
Running the retirement procedure do not create error, but the successor procedure does create an error.
I did not copy-paste everything because I don't think it is useful as the two procedure are exactly the same. The other calculations use global variables and lists created in other procedures in the observer context.
Here-below is the dispatch-parcels procedure that regards to concerned patches from the beginning.
to dispatch-parcels
;; this regards the patches with seed = 1 that has been processed in the successor procedure. But doesn't work as for updating the age and death of the agent
set seed 0
set age 0
set death 0
;; if there is no successor, the parcels of the farm are distributed along the closest parcels : one farm can distribute its own parcels to multiple different farms
ask patches with [ ID-farm = [ID-farm] of myself]
;; for each parcel, finds the closest parcel and use the ID-farm as the new ID-farm, same for the region in case it changes.
[
set ID-farm ([ID-farm] of (min-one-of patches with [(ID-farm != 0) AND (ID-farm != [ID-farm] of myself)] [distance myself] ))
set region ([region] of (min-one-of patches with [(region != 0) AND (region != [region] of myself)] [distance myself] ))
]
end
I also tried to the successor procedure with the same final command line as from the retirement procedure but I get the same error message. So there should be something "hidden" somewhere about this successor procedure.
Any insight about the likely source of error, what I should more attention to ?
Thanks for your time.
I finally figured out what was wrong. It was so obvious that it became invisible and I'm a bit embarrased.
I'd like to share my answer anyway because it might opened the eyes of tired beginners like me.
In order to test this part of my code, I created a button to only test the successor procedure, which was in observer context, which was not possible with the commands I wrote. That's just it.
Related
I have people moving forward and I need the simple code to let these people when they intersect with each other ( if the number of people in the patch exceed certain number ---> lead to danger?
the second behavior: people need to walk then stop for some time to do some task then complete their walking.. how can I code this ? is there any idea for that?
the message from the below code tell that : Nothing named >=2 has been defined?
to go
ask pilgrims
[fd 1]
if any? other turtles-here >=2 [ set in-danger? true]
I am trying to use the ifelse statement to supply conditions to global variable called "space-death?" implemented at the netlogo interface as a switch.
to Pass-Away
ifelse space-death? [
ask turtles[ Pass-Away-Space ]
ask turtles[ Pass-Away-Time]
]
]
end
In the code, I implement a turtle mortality procedure called "Pass-Away" which when run, asks if the space-death switch is turned on at the netlogo interface. If the space-death switch is on, then it asks the turtles to call and run another netlogo procedure block called "Pass-Away-Space" and if it not, regular turtle death ensues by calling another procedure block dubbed "Pass-Away-Time."
However, I am getting the following error message:
IFELSE expected three inputs, a TRUE/FALSE, a command block and a command block
Can one see where I may have gone wrong and correct this code accordingly. Alternatively, if there is a better code-based way to implement this logic other than an interface global, please indulge me in your response.
globals [space-death?]
to setup
ca
set space-death? true
crt 100
end
to go
ask turtles [pass-away]
end
to pass-away
ifelse space-death? [
Pass-Away-Space
][
Pass-Away-Time
]
end
to pass-away-space
;your code here
end
to pass-away-time
;your code here
end
I am trying to implement an auction concept in netlogo - it is similar to the dining philosophers problem program.
My program deals with computers and processors that correspond to philosophers and forks in the dining philosopher program. In the philosophers program a user needs 2 forks to eat but in computers and processors, one computer needs one processor to work.
The states defined in my program are IDLE, NEED, USING, corresponding to THINKING, HUNGRY, EATING in the philosopher program.
Currently, my program goes to the point where all computers state changes to NEED. I am having issues in acquiring of server for the computers.
The code snippet is -
// ... lines of code for declaration etc
.
.
.
to update
if state = "IDLE" [
if random-float 1.0 < hungry-chance [
set state "NEED"
]
stop
]
if state = "USING" [
set total-used (total-used + 1)
if random-float 1.0 < full-chance
[ release-servers ]
set state "IDLE"
stop
]
if state = "NEED"
[ acquire-servers ]
if we've got both forks, eat.
if got? servers
[ set state "USING" ]
stop
end
//lines of code in between
.
.
to acquire-servers ;; philosopher procedure
ask servers [
if [owner] of servers = nobody[
set owner myself
move-to owner
set heading [heading] of owner
]
]
end
// lines of code at end
First, you need to change your if for testing state into ifelse and remove the stop commands. That way, the computer will find its correct state and do the relevant procedures and then not look at the other states.
Second, the acquire-servers procedure currently assigns all the servers to the first computer that needs one. You probably want a procedure that looks more like:
to acquire-one-server
let candidates servers with [ owner = nobody ]
if any? candidates
[ ask one-of candidates
[ set owner myself
move-to owner
set heading [heading] of owner
]
]
end
I have a grid of 10x10 nodes where all adjacent nodes are linked to create a graph of 180 links - i.e:
What I hope to do is create a procedure which will break x% of these links, but importantly do so without creating any isolated subgraphs - that is, so that any 1 of the 100 nodes remain accessible from all other 99 nodes - i.e.
I initially (and naively) thought I could do something like the following:
ask n-of 45 nodes with [count my-links > 1]
[
ask one-of my-links [die]
]
However, this does not prevent sub-graphs from being orphaned from the main graph - i.e.
Another option might be to repeatedly ask single links to die and then check the total number of graphs does not exceed 1 - if it does, recreate the link and choose another to break. However, (1) this does not seem particularly elegant; and (2) I have been unable to find a way to count the number of distinct graphs using the inbuilt link or nw procedures.
I do think that part of my problem is not knowing the correct terminology for these subgraphs/isolates/cliques etc...
If anyone has any ideas on how this might be done (or can correct my woefully inadequate comprehension of graph theory terminology) it would be much appreciated.
Many thanks for the heads-up re nw:weak-component-clusters - I wasn't aware of that.
I have now implemented the following simple recursive procedure which will kill a link and if that link splits the graph recreate it and recall the procedure. This works well for what I wanted to do. Do note however that if you run this enough times you will end up stuck in a recursive loop as there will be no further links to break without splitting the graph and the procedure will keep calling itself.
to breakLink
let breakCandidate one-of links
let end1Candidate [end1] of breakCandidate
let end2Candidate [end2] of breakCandidate
ask breakCandidate [die]
if (length nw:weak-component-clusters > 1)
[
ask end1Candidate
[
create-link-with end2Candidate
breakLink
]
]
end
Cheers
For the solution you thought of, you can use the nw extension to check if there's still a path between the nodes you just disconnected by checking if nw:distance-to returns false or a number.
Alternatively, you can count the number of connected components.
I think removing the link and testing connectedness is a perfectly reasonable way to go. Any algorithm you implement will have to awkwardly pretend the link doesn't exist anyway, so will likely be more complicated than just removing the thing.
Edit: Adding code for the distance version to clarify:
to break-link
let break-candidate one-of links
let end-one [end1] of break-candidate
let end-two [end2] of break-candidate
ask break-candidate [die]
if [nw:distance-to end-two] of end-one = false [
ask end-one [ create-link-with end-two ]
break-link
]
end
Not sure if this or the nw:weak-component-cluster version will be faster. That will likely depend on the size of the network.
I have a code in which juveniles (juvis juvi) become adults (adults adult). The current way I have it is that juvis change breed to adults at a set age (determined by a turtles own, j-age). However I have a turtles own for adults (a-age) which I want to be Zero when the juvis change breed to adults. Does this happen automatically, or do I have to add code along the lines of "set a-age 0". I have tried putting that in in various guises and places but always get errors. Current code is as follows:
to emergence
ask juvis
[if j-age = (juvenile-period * 24) [set breed adults]]
end
any advice is appreciated. thank you.
When you change breed, any variables owned by the current breed that were not owned by the previous breed are set to 0.
You can test this yourself--just add a SHOW command to show the variable you are curious about!