how to change number of #Core.periodic(30) - volttron

I make a new agent, and I will call every 30 seconds through Core.periodic(30).
And I write such as #Core.periodic(self.heart_beat), but this is not operate.
(heart_beat is config file's variable.)
I don't know how to solve it.
enter image description here

#Core.periodic is a decorator (you can tell by the # at the start of the line). It is supposed to be used like this:
#Core.periodic(30)
def heart_beat(self):
#Do heartbeat stuff here
If you need to do something dynamic you can hook up the callback during run time with self.core.periodic. This allows you to change the setting dynamically and stop the periodic function later if needed.
self.heart_beat_greenlet = self.core.periodic(30, self.heart_beat)
Later you can call self.heart_beat_greenlet.kill() to stop the periodic function.

Related

How do I request a scan on a Wi-Fi device using libnm?

The documentation suggests I use nm-device-wifi-request-scan-async, but I don't understand how to understand when it's has finished scanning. What's the correct second parameter I should pass, how is it constructed and what do I pass to nm-device-wifi-request-scan-finish?
I've tried using nm-device-wifi-get-last-scan and determining whether the scan has just happened or the last scan was a long time ago, but it doesn't seem to update the time of the scan - i.e., after requesting the scan and printing out the time between nm-utils-get-timestamp-msec and the last scan, it only increases and and decreases only if I restart the whole program, for some reason...
All I really need is to request a scan every x seconds and understand whether it has happened or not. The deprecated synchronous functions seem to have allowed this with callback functions, but I don't understand async :(
nm_device_wifi_request_scan_async() starts the scan, it will take a while until the result is ready.
You will know when the result is ready when the nm_device_wifi_get_last_scan() timestamp gets bumped.
it only increases and and decreases only if I restart the whole program, for some reason...
last-scan should be in clock_gettime(CLOCK_BOOTTIME) scale. That is supposed to never decrease (unless reboot). See man clock_gettime.
but I don't understand async
The sync method does not differ from the async method in this regard. They both only kick off a new scan, and when they compete, NetworkManager will be about to scan (or start shortly). The sync method is deprecated for other reasons (https://smcv.pseudorandom.co.uk/2008/11/nonblocking/).

Timer to represent AI reaction times

I'm creating a card game in pygame for my college project, and a large aspect of the game is how the game's AI reacts to the current situation. I have a function to randomly generate a number within 2 parameters, and this is how long I want the program to wait.
All of the code on my ai is contained within an if statement, and once called I want the program to wait generated amount of time, and then make it's decision on what to do.
Originally I had:
pygame.time.delay(calcAISpeed(AIspeed))
This would work well, if it didn't pause the rest of the program whilst the AI is waiting, stopping the user from interacting with the program. This means I cannot use while loops to create my timer either.
What is the best way to work around this without going into multi-threading or other complex solutions? My project is due in soon and I don't want to make massive changes. I've tried using pygame.time.Clock functions to compare the current time to the generated one, but resetting the clock once the operation has been performed has proved troublesome.
Thanks for the help and I look forward to your input.
The easiest way around this would be to have a variable within your AI called something like "wait" and set it to a random number (of course it will have to be tweaked to your program speed... I'll explain in the code below.). Then in your update function have a conditional that waits to see if that wait number is zero or below, and if not subtract a certain amount of time from it. Below is a basic set of code to explain this...
class AI(object):
def __init__(self):
#put the stuff you want in your ai in here
self.currentwait = 100
#^^^ All you need is this variable defined somewhere
#If you want a static number as your wait time add this variable
self.wait = 100 #Your number here
def updateAI(self):
#If the wait number is less than zero then do stuff
if self.currentwait <= 0:
#Do your AI stuff here
else:
#Based on your game's tick speed and how long you want
#your AI to wait you can change the amount removed from
#your "current wait" variable
self.currentwait -= 100 #Your number here
To give you an idea of what is going on above, you have a variable called currentwait. This variable describes the time left the program has to wait. If this number is greater than 0, there is still time to wait, so nothing will get executed. However, time will be subtracted from this variable so every tick there is less time to wait. You can control this rate by using the clock tick rate. For example, if you clock rate is set to 60, then you can make the program wait 1 second by setting currentwait to 60 and taking 1 off every tick until the number reaches zero.
Like I said this is very basic so you will probably have to change it to fit your program slightly, but it should do the trick. Hope this helps you and good luck with your project :)
The other option is to create a timer event on the event queue and listen for it in the event loop: How can I detect if the user has double-clicked in pygame?

Breakable loop in Scratch?

How do you make a breakable loop in Scratch? I'm using Scratch 2.0 and can't find any good way to make a loop breakable, from inside of the loop itself.
Disclaimer:
There is no perfect way to do it. If you can possibly stand this true fact then feel free to continue.
There are a few different ways you could do it.
With repeat until
The first and most simple one follows this:
But this isn't technically part of the script - it's just repeating until some value returns true.
With a custom block (stop this script)
In order to do it inside of the script, you'll need to use a sneaky little trick with custom blocks.
Create a custom block called whatever you want - but probably along the lines of "breakable loop". Inside of it, create this script:
By using stop script we are breaking out of the script that is currently running - which, according to Scratch, is the custom block.
See the result! (as scratchblocks)
With broadcast and wait
You could also use a broadcast-and-wait method, very similar to above:
Though I highly suggest you don't use this method, as if any other sprites have breakable loops you'll need to rename each one, which can be tedious after using a lot of loops in a lot of sprites!
(Note this bug has been fixed in version 442 of the editor and such the following no longer applies.)
Help! My project is lagging a bunch now!
As #foi has noticed, if your code must be run inside of a frame you probably checked run without screen refresh. Unfortunately, due to a bug in the Scratch player, this causes the program to essentially break after the stop this script block has been activated. How can you handle this?
It follows the same principle you use when you use a run without screen refresh custom block inside of a forever loop - the loop doesn't use screen refresh while the inside does, allowing for instant animations whether or not one is using turbo mode.
Here's an example - the image is really too long to be embedded, so see it here instead.
You can make a variable inside or outside of the repeat and make your script like this:
repeat until [[my variable] = [e.g: 1]]
your code
your code
your code
your code
end of repeat until
For a "repeat until" block the simplest way would be to "or" your normal until condition with the break condition in the until.
By adding an incremeting loop counter variable in the loop you can use a "repeat until" to replicate the function of a "repeat n times" block
By using a "repeat until" block with only your break condition you get the equivalent of a "forever" block
If you need another script/ sprite to trigger the break then a public variable will let you break the loop from anywhere and let a single condition break loops for different sprites.
I'd post an image of the blocks but this is my first reply and the site won't let me!
good luck
You can use these few ways to do it...
conditional loop
stop this script
if then else, in the else section, put nothing
I would prefer to use the first method, as it requires less blocks and for the first method, you can still add in code that will be executed after the loop has stopped executing.
You can make it repeat x times or make it have a certain point where it stops, such as another variable changing.
Otherwise, I don't think there is a wat to do that.
Use the repeat until block. Then put in an equals block or whatever into the boolean part. Then inside that repeat until block, put a stop this script block.
Hope this helps :D

Create a non-blocking timer to erase data

Someone can show me how to create a non-blocking timer to delete data of a struct?
I've this struct:
struct info{
char buf;
int expire;
};
Now, at the end of the expire's value, I need to delete data into my struct. the fact is that in the same time, my program is doing something else. so how can I create this? even avoiding use of signals.
It won't work. The time it takes to delete the structure is most likely much less than the time it would take to arrange for the structure to be deleted later. The reason is that in order to delete the structure later, some structure has to be created to hold the information needed to find the structure later when we get around to deleting it. And then that structure itself will eventually need to be freed. For a task so small, it's not worth the overhead of dispatching.
In a difference case, where the deletion is really complicated, it may be worth it. For example, if the structure contains lists or maps that contain numerous sub-elements that must be traverse to destroy each one, then it might be worth dispatching a thread to do the deletion.
The details vary depending on what platform and threading standard you're using. But the basic idea is that somewhere you have a function that causes a thread to be tasked with running a particular chunk of code.
Update: Hmm, wait, a timer? If code is not going to access it, why not delete it now? And if code is going to access it, why are you setting the timer now? Something's fishy with your question. Don't even think of arranging to have anything deleted until everything is 100% finished with it.
If you don't want to use signals, you're going to need threads of some kind. Any more specific answer will depend on what operating system and toolchain you're using.
I think the motto is to have a timer and if it expires as in case of Client Server logic. You need to delete those entries for which the time is expired. And when a timer expires, you need to delete that data.
If it is yes: Then it can be implemented in couple of ways.
a) Single threaded : You create a sorted queue based on the difference of (interval - now ) logic. So that the shortest span should receive the callback first. You can implement the timer queue using map in C++. Now when your work is over just call the timer function to check if any expired request is there in your queue. If yes, then it would delete that data. So the prototype might look like set_timer( void (pf)(void)); add_timer(void * context, long time_to_expire); to add the timer.
b) Multi-threaded : add_timer logic will be same. It will access the global map and add it after taking lock. This thread will sleep(using conditional variable) for the shortest time in the map. Meanwhile if there is any addition to the timer queue, it will get a notification from the thread which adds the data. Why it needs to sleep on conditional variable, because, it might get a timer which is having lesser interval than the minimum existing already.
So suppose first call was for 5 secs from now
and the second timer is 3 secs from now.
So if the timer thread only sleeps and not on conditional variable, then it will wake up after 5 secs whereas it is expected to wake up after 3 secs.
Hope this clarifies your question.
Cheers,

Why does it increase each time?

I want to understand why the number of timer keeps increasing whenever it is in use.
Should it start from a fresh number each time?
And why does it increase 2 or 4 each but not 1?
$(document).ready(function(){
endAndStartTimer();
});
var timer;
function endAndStartTimer() {
window.clearTimeout(timer);
//var millisecBeforeRedirect = 10000;
timer = window.setTimeout(function(){alert('Hello!');},1000);
alert(timer);
}
Do I need window.clearTimeout(timer); inside the function? What would it be wrong if I d
you can try it here.
Thanks.
Some simple facts
You don't have to call clearTimeout before setting one. At least not in the code you provided.
When I run your JSFiddle in FF4 it always reports 2
Timer IDs are generated by Javascript engine implemented in the browser so you don't have much control over it. Whatever it returns is value that you have to use to clear it. I haven't tested it but it may as well be that these ID generators are implement in a different way. Although the simplest (=fastest) way is by simply incrementing the ID of the last timer ID.
The method returns unique timer ID. The only purpose is to give you a handle to use it with clearTimeout. You can't control what id is generated.

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