I tried to solve the problem, but I got a different table than the table that xilinx shows. I attatched both my answer and real answer. Xilinx shows that "out" is 'U' until 36ns, after 36ns, it is '1'. Can anyone help me about why the "out" graphics is not assigned any value before 36ns?(I think it should be assigned first at 20 ns).
my answer
question
This turned out to be a really good question. I initially thought you had done something wrong when simulating, but then I ran my own simulation and got the same result.
It turns out that the a <= b after x assignment uses something called the "inertial time model" by default. In this mode scheduled events will be cancelled if b changes again before x time has passed. The purpose is to filter pulses shorter than the specified delay. In your case this is what the simulator will do:
At t=0, out is scheduled to change to 1 at t=20.
At t=12, tem1 or tem2 changes to 0. The scheduled change at t=20 is cancelled and a new change to 0 is scheduled at t=32.
At t=16, tem1 or tem2 changes back to 1. Again the scheduled change is cancelled and a new change is scheduled at t=36.
After this tem1 or tem2 remains at 1, so the change at t=36 is executed and out finally changes from U.
You can change to the "transport delay model" using out <= transport tem1 or tem2 after 20 ns; In this case your drawn waveform will match with simulation.
Related
i am new to pinescript but i am facing an huge problem when i try to work with time.
The problem is:
I have an indicator that shows buy (or sell) on the current candlestick but sometimes it disappear. I wanted to add a control where if the buy is true for more than 15 second (average time where the signal will no longer disappear), the alert will send me a notification.
I tried so many things like putting the 'timenow' in a variable and compare as follow
BuyTime := timenow
If timenow - BuyTime >= 15000
RealBuy = true
And many more things that i dont perfectly remember..
I dont know why but i wasn't able to get it to work, any suggestion please?
Thanks in advance
I am fairly new to Prometheus alertmanager and had a doubt regarding firing alerts only during a particular period
I have a microservice which receives a file and does some processing on it, which is only invoked when it gets a message through a Kafka queue. The aforementioned is supposed to come every day between 5 am and 6 am(UTC time). The microservice has a metric which is incremented by 1 every time it receives a file. I want to raise an alert if it does not receive a file in the interval. I have created a query like this :
expr : sum(increase(metric_name[1m]) and on() hour(vector(time()))==5) < 1
for: 1h
My questions:-
1) Is it correct or is there a better way to do it
2) In case of no update, will it return 0 or "datapoints not found"
3) Is increase the correct function as it tends to give results in decimals due to extrapolation, but I understand if increase is 0, it will show 0
I can't really play around with scrape_intervals, which is set at 30s.
I have not run this expression but I expect it will cause an alert to fire at 06:00 only and then go off at 06:01. It is the only time the expression would hold true for one hour.
Answering your questions
It is correct if what you want is a single fire of alert (sending a mail by example) but then no longer firing. Even with that, the schedule is a bit tight and may get hurt by alertmanager delay causing the alert to be lost.
In case of no increase, you will get the expression will evaluate to 0. It will be empty when there is an update
Increase is the right function. It even takes into account reset of the counter.
Answering if there is a better way to do it.
Regarding your expression, you can have the same result, without for clause, with:
expr: increase(metric_name[1h])==0 and on() hour()==6 and on() minute()<1
It reads a : starting at 6am and for 1 minutes, if there was no increase of metric over the lasthour.
Alerting longer
If you want the alert to last longer (say for the day and you silence it when it is solved), you can use sub-queries;
expr: increase((metric and on() hour()==5)[18h:])==0 and on() hour()>5
It reads as : starting at 6am (hour()>5), compute the increase over 5-6am for the next 18 hours. If you like having a pending, you can drop the trailing on() hour()>5 and use a for: 1h clause.
If you want to alert until a file is submitted and thus detect a resolution, simply transform the expression to evaluate the increase until now:
expr: increase((metric and on() hour()>5)[18h:])==0 and on() hour()>5
I need to collect event logs from Windows those are logged before 10 seconds. Using pull subscription I could collect already saved logs before execution of program and saving logs while program is running. I tried with the code available on MSDN:
Subscribing to Events
"I need to start to collect the event logged 10 seconds ago". Here I think I need to set value for LPWSTR pwsQuery to achieve that.
L"*[System/Level= 2]" gives the events with level equal to 2.
L"*[System/EventID= 4624]" gives events with eventID is 4624.
L"*[System/Level < 1]" gives events with level < 2.
Like that I need to set the value for pwsQuery to get event logged near 10 seconds. Can I do in the same way as above? If so how? If not what are the other ways to do it?
EvtSubscribe() gives you new events as they happen. You need to use EvtQuery() to get existing events that have already been logged.
The Consuming Events documentation shows a sample query that retrieves events beginning at a specific time:
// The following query selects all events from the channel or log file where the severity level is
// less than or equal to 3 and the event occurred in the last 24 hour period.
XPath Query: *[System[(Level <= 3) and TimeCreated[timediff(#SystemTime) <= 86400000]]]
So, you can use TimeCreated[timediff(#SystemTime) <= 10000] to get events in the last 10 seconds.
The TimeCreated element is documented here:
TimeCreated (SystemPropertiesType) Element
The timediff() function is described on the Consuming Events documentation:
The timediff function is supported. The function computes the difference between the second argument and the first argument. One of the arguments must be a literal number. The arguments must use FILETIME representation. The result is the number of milliseconds between the two times. The result is positive if the second argument represents a later time; otherwise, it is negative. When the second argument is not provided, the current system time is used.
On the MIT App Inventor (similar but not the same to Scratch), I need to create a timer that can be reset when an action happens to complete an App. But, I have been unable to find a way to make a resetable timer. Is there a way using this piece of software? This is a link to the App Inventor.
The first 4 blocks are the codes for when the player interacts/clicks one of the 4 colored boxes.
The last block is the code outside of the 4 .Click blocks.
Btw. there is a lot of redundancy in your blocks, see Enis' tips here how to simplify this...
If you want to reset the clock, just set Clock.TimerEnabled = false and then set
Clock.TimerEnabled = true again and the clock will restart
see also the following example blocks (let's assume, you have a clock component and the timer interval is 10 seconds)
in the example I reset the clock after 5 seconds and as you can see, the clock starts from the beginning...
You can download the test project from here
Can't get the max_failures idea. From the documentation:
This attribute specifies the number of times a job can fail on consecutive scheduled runs before it is automatically disabled.
So, let's suppose I have a schedule. Its running count is 100. Its failure count is 18. Its max failures is 20.
Current run has finished successfully.
I expect: if I will break it - it will run exactly 20 times on state FAILED after which it will be changed to BROKEN
What I get: it runs 2 times so failure count is 20 and despite the fact it were just 2 consecutive runs the schedule is changed to state BROKEN.
What have I missed?
I think "consecutive scheduled runs" means exactly that. If it succeeds, the failure count should be reset to 0.
EDIT
Guess I was wrong, sorry.
Reading up: http://download.oracle.com/docs/cd/E11882_01/server.112/e17120/schedadmin004.htm
As per Gary's comment - looks like you need to reset the failure count manually.