It is possible that on Azure functions beta the timer has a bug or did I something wrong?
My cron timer in the application settings was this:
59 23 * * * *
and the last run was on 2018-02-21T17:23:59.0307645+00:00
How should I set the cron timer if I want to have every day at 23:59?
The expression you currently have (59 23 * * * *) means "every hour at 23 minutes and 59 seconds). What you need to use instead is 0 59 23 * * *. Note that by default, this will be treated as UTC time.
Be aware that CRON expressions have lots of dialects, and I don't think the other answer will work. My answer is specifically for Azure Functions, which uses ncrontab (the flavor of it that supports the 'seconds' field).
Everyday at 23:59: 0 59 23 1/1 * ? *
Source
Related
How can i start Hangfire every 00 and 30 minutes?
For Examle, i start project 13:20, Hangfire must start 13:30, 14:00, 14:30, 15:00 ... etc.
I know how to start hangfire every 30 minutes expression ("*/30 * * * *") but my hangfire need to start not only every 30 minutes but also at exact xx:30 and xx:00 times.
What should be my cron job expression?
https://crontab.cronhub.io/
0,30 * * * *
This is not a coding-related question though.
you Should use this
RecurringJob.AddOrUpdate(() => Console.Write("Recurring"), "*/30 * * * *");
Reference to my question in Hangfire forums: http://discuss.hangfire.io/t/how-to-create-cron-job-that-is-executing-every-15-minutes/533
I did profiling for my console application using Unity IOC and a lot of calls using HttpCLient. How to understand it?
Function Name, Inclusive Samples, Exclusive Samples, Inclusive Samples %, Exclusive Samples %
Microsoft.Practices.Unity.UnityContainer.Resolve 175 58 38.89 12.89
Microsoft.Practices.Unity.UnityContainer..ctor 29 29 6.44 6.44
System.Runtime.CompilerServices.AsyncTaskMethodBuilder1[System.DateTime].Start 36 13 8.00 2.89
Microsoft.Practices.Unity.UnityContainerExtensions.RegisterInstance 9 9 2.00 2.00
System.Net.Http.HttpClientHandler..ctor 9 9 2.00 2.00
System.Net.Http.HttpMessageInvoker.Dispose 9 9 2.00 2.00
System.Activator.CreateInstance 20 8 4.44 1.78
Microsoft.Practices.Unity.ObjectBuilder.NamedTypeDependencyResolverPolicy.Resolve 115 3 25.56 0.67
What means that inclusive samples for Microsoft.Practices.Unity.UnityContainer.Resolve are 38,89 but exclusive are 12,89? Is it ok? Not too much?
"Inclusive" means "exclusive time plus time spent in all callees".
Forget the "exclusive" stuff.
"Inclusive" is what it's costing you.
It says UnityContainer.Resolve is costing you 39% of time,
and Unity.ObjectBuilder.NamedTypeDependencyResolverPolicy.Resolve is costing you 26%.
It looks like the first one calls the second one, so you can't add their times together.
If you could avoid calling all that stuff, you would save at least 40%, giving you a speedup of at least 100/60 or 1.67 or 67%
By the way, that Unity stuff, while not exactly deprecated, is no longer being maintained.
why rounds C# this calculation up?
500 -> 501
MessageBox.Show(Math.Ceiling(1 / (4 * 1 - 4 * 0.9) * 200).ToString());
Returns.
---------------------------
---------------------------
501
---------------------------
OK
---------------------------
I dont know why.
Excel doesnt do this, too.
I need the ceiling function for the fomula which returns 500 instead 501.
I could use this instead. But i would know if there is another solution and why C# do this.
MessageBox.Show(Math.Ceiling(Math.Floor((1 / (4 * 1 - 4 * 0.9) * 200) * 100) / 100).ToString());
The problem is that 500 is actually not 500 but rather 500.0000000001 (or something similar) due to using floating point operations.
To solve this issue, use decimal instead of double.
MessageBox.Show(Math.Ceiling(1.0M / (4.0M * 1.0M - 4.0M * 0.9M) * 200.0M).ToString());
See What every Computer Scientist should know about Floating-Point Arithmetic for further information, or take a look at this website for a simpler explanation.
I'm sort of new at this and I'm writing a small application to read data from a voltmeter. It's a RadioShack Digital Multimeter 46-range. The purpose of my program is to perform something automatically when it detects a certain voltage. I'm using C# and I'm already familiar with the SerialPort class.
My program runs and reads the data in from the voltmeter. However, the data is all unformatted/gibberish. The device does come with its own software that displays the voltage on the PC, however this doesn't help me since I need to grab the voltage from my own program. I just can't figure out how to translate this data into something useful.
For reference, I'm using the SerialPort.Read() method:
byte[] voltage = new byte[100];
_serialPort.Read(voltage, 0, 99);
It grabs the data and displays it as so:
16 0 30 0 6 198 30 6 126 254 30 0 30 16 0 30 0 6 198 30 6 126 254 30 0 30 16 0 3
0 0 6 198 30 6 126 254 30 0 30 16 0 30 0 6 198 30 6 126 254 30 0 30 16 0 30 0 6
198 30 6 126 254 30 0 30 24 0 30 0 6 198 30 6 126 254 30 0 30 16 0 30 0 254 30 6
126 252 30 0 6 0 30 0 254 30 6 126 254 30 0
The space separates each element of the array. If I use a char[] array instead of byte[], I get complete gibberish:
▲ ? ? ▲ ♠ ~ ? ▲ ♠ ▲ ? ? ▲ ♠ ~ ? ▲ ♠ ▲ ? ? ▲ ♠ ~ ? ▲ ♠
Using the .ReadExisting() method gives me:
▲ ?~?♠~?▲ ▲? ▲ ?~♠~?▲ ?↑ ▲ ??~♠~?▲ F? ▲ ??~♠~?▲ D? ▲ ??~♠~?▲ f?
.ReadLine() times out, so doesn't work. ReadByte() and ReadChar() just give me numbers similar to the Read() into array function.
I'm in way over my head as I've never done something like this, not really sure where else to turn.
It sounds like you're close, but you need to figure out the correct Encoding to use.
To get a string from an array of bytes, you need to know the Code Page being used. If it's not covered in the manual, and you can't find it via a google/bing/other search, then you will need to use trial and error.
To see how to use GetChars() to get a string from a byte array, see Decoder.GetChars Method
In the code sample, look at this line:
Decoder uniDecoder = Encoding.Unicode.GetDecoder();
That line is specifically stating that you are to use the Unicode code page to get the correct code page.
From there, you can use an override of the Encoding class to specify different Code Pages. This is documented here: Encoding Class
If the Encoding being used isn't one of the standards, you can use the Encoding(Int32) override in the Constructor of the Encoding class. A list of valid Code Page IDs can be found at Code Pages Supported by Windows
There are two district strategies for solving your communications problem.
Locate and refer to appropriate documentation and design\modify a program to implement the specification.
The following may be appropriate, but are not guaranteed to describe the particular model DVM that you have. Nonetheless, they MAY serve as a starting point.
note that the authors of these documents comment that the Respective models may be 'visually identical', but also comments that '"Open-source packages that reportedly worked on LINUX with earlier RS-232 models do not work with the 2200039"
http://forums.parallax.com/attachment.php?attachmentid=88160&d=1325568007
http://sigrok.org/wiki/RadioShack_22-812
http://code.google.com/p/rs22812/
Try to reverse engineer the protocol. if you can read the data in a loop and collect the results, a good approach to reverse engineering a protocol, is to apply various representative signals to the DVM. You can use a short-circuit resistance measurements, various stable voltage measurements, etc.
The technique I suggest is most valuable is to use an automated variable signal generator. In this way, by analyzing the patterns of the data, you should be more readily be able to identify which points represent the raw data and which points represent stable descriptive data, like the unit of measurements, mode of operation, etc.
Some digital multimeters use 7 bit data transfer. You should set serial communication port to 7 data bits instead of standard 8 data bits.
I modified and merged a couple of older open source C programs together on linux in order to read the data values from the radio shack meter whose part number is 2200039. This is over usb. I really only added a C or an F on one range. My program is here, and it has the links where I got the other two programs in it.
I know this example is not in C#, but it does provide the format info you need. Think of it is as the API documentation written in C, you just have to translate it into C# yourself.
The protocol runs at 4800 baud, and 8N1 appears to work.
I'll try to explain this problem the best way i can with code:
double power = 5000;
//picked up 5 power ups, now need to increase power by 10% per powerup
power += 5 * (power * .10);
//later on...ran into 5 power downs need to decrease power back to initial hp
power -= 5 * (power * .10);//7500 - 3750 -- doesn't work
So what i need is a scaleable solution that gets back to the original value using only the count. Any ideas?
The best way to do this is using a function. It doesn't have to look exactly like this, but:
class Whatever
{
private double basePower = 5000;
public int numPowerUps = 5;
public double GetActualPower()
{
return basePower + (numPowerUps * basePower * 0.1);
}
}
Just change numPowerUps back to 0 when they run out. This way, it looks a whole lot neater.
An aside:
The reason it's not working is because of the fact that adding and then subtracting percentages doesn't work. For instance:
1. What is 10% of 100? --> 10
2. Add that to the 100 --> 110
3. What is 10% of 110? --> 11
4. Subtract that from 110 --> 99
You'll always end up with 99% of your original value. If you really want to take a shortcut, you could instead do this:
1. What is 10% of 100? --> 10
2. Add that to the 100 --> 110
3. What is (100/11) = 9.09090909...% of 110? --> 10
4. Subtract that from 110 --> 100
But then you're potentially susceptible to floating point errors. The function way of doing it is not only neater and clearer, but potentially less error-prone.
To reverse a %age increase, you must divide by the original %age, not subtract.
i.e.:
100 + 5% = 100 * 1.05 = 105
to reverse it:
105 / 1.05 = 100
The more usual '5% off' formula would instead give you:
105 - 5% = (105 * 0.95) = 99.75
To power up:
power <- power * (1 + count * percent);
eg: 5000 * (1 + 5 * 0.1)
5000 * 1.5
7500
To power back down:
power <- power / (1 + count * percent)
eg: 7500 / (1 + 5 * 0.1)
7500 / 1.5
5000
Let's take a more complicated example, 17 power ups, each giving 3% to an intial 1234 power:
1234 * (1 + 17 * 0.3)
= 1234 * (1 + 5.1)
= 1234 * 6.1
= 7527.4
7527.4 / (1 + 17 * 0.3)
= 7527.4 / (1 + 5.1)
= 7527.4 / 6.1
= 1234
It actually looks pretty simple when you write it out like that.
This doesn't work because the two percentages are not taken from the same number. They're taken from the same variable, but not the same number.
The first time, power * 0.10 is 500, and 5*500=2500 so the power will be 5000+2500=7500. Now, the power is 7500, so power * 0.10 is 750. 5*750 = 3750 and 7500-3750=3750 and not 5000 like you started out with.
So apparently, what you want is not really to in/decrease by a percentage of the current power. Perhaps it would be better to set a base power (let's say 5000) and an actual power. Then when you in/decrease, you use actualPower = actualPower + 5*0.1*basePower; or something. Or you just accept that five power downs after five power ups does not get you back to initial hp.
I'm going to suspect that what you mean by "doesn't work" is that the value for power does not end up to be exactly 3750.
This is due to floating-point rounding errors, as floating point values such as double and float are not able to be represented exact values.
If exact values are needed, then using decimal or int would be a better solution, as they are designed to handle exact values.
Edit The actual issue here is not a floating-point rounding error, but an issue noted in Smashery's answer.