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""" A [GFF parser script][1] in Python for [www.VigiLab.org][2] Description: - That performs buffered reading, and filtering (see: @filter) of .GFF input file (e.g. "[./toy.gff][3]") to keep only rows whose field (column) values are equal to "transcript...

For example, imagine a screen with 3 sections, laid out like this: The blue box might be given a margin of 4,4,0,0. The green box might be given a margin of 4,4,4,0. The purple box margin would be 4,4,4,4. Here's the XAML: (I'm using a grid to achieve the layout; but this design principle applies...

To generalise what we've demonstrated above: individual things contain a fixed margin of "half-the-whitespace", and the container they are held in should have a padding of "half-the-whitespace". You can apply these styles in your application resource dictionary, and then you won'...

Sometimes Android's logcat is running infinitely with errors coming from some process not own by you, draining battery or just making it hard to debug your code. A convenient way to fix the problem without restarting the device is to locate and kill the process causing the problem. From Logcat 03...

// This is a MiDI clk generator. This takes a #defined BPM and // makes the appropriate clk rate. The queue is used to let other messages // through, but allows a clock to go immediately to reduce clock jitter #define QUEUE_DEPTH 128 #define BPM 121 #define MIDI_SYSRT_CLK 0xF8 // clock...

Let's first create a simple "Hello world!" MailboxProcessor which processes one type of message and prints greetings. You'll need the message type. It can be anything, but Discriminated Unions are a natural choice here as they list all the possible cases on one place and you can easily us...

You can use Scan or TryScan methods to look for specific messages in the queue and process them regardless of how many messages are before them. Both methods look at the messages in the queue in the order they arrived and will look for a specified message (up until optional timeout). In case there i...

Blocking Operation Example let loop = (i, max) => { while (i < max) i++ return i } // This operation will block Node.js // Because, it's CPU-bound // You should be careful about this kind of code loop(0, 1e+12) Non-Blocking IO Operation Example let i = 0 const step = max =...

So let's say again that you have the following model: public class Person { public int PersonId { get; set; } public string Name { get; set; } } public class Car { public int CarId { get; set; } public string LicensePlate { get; set; } } public class MyDemoContext : DbContext ...

Mapping one-to-one (when both sides are required) is also a tricky thing. Let's imagine how this could be represented with foreign keys. Again, a CarId in People that refers to CarId in Car, and a PersonId in Car that refers to the PersonId in People. Now what happens if you want to insert a car r...

And to finish off, let's briefly look at the case when both sides are optional. By now you should be really bored with these examples :), so I'm not going into the details and play with the idea of having two FK-s and the potential problems and warn you about the dangers of not enforcing these rule...

Basics require('http').globalAgent.maxSockets = 25 // You can change 25 to Infinity or to a different value by experimenting Node.js by default is using maxSockets = Infinity at the same time (since v0.12.0). Until Node v0.12.0, the default was maxSockets = 5 (see v0.11.0). So, after more tha...

""" CannyTrackbar function allows for a better understanding of the mechanisms behind Canny Edge detection algorithm and rapid prototyping. The example includes basic use case. 2 of the trackbars allow for tuning of the Canny function and the other 2 help with understanding h...

So let's say you have two different entities, something like this: public class Person { public int PersonId { get; set; } public string Name { get; set; } } public class Car { public int CarId { get; set; } public string LicensePlate { get; set; } } public class MyDemoCon...

In the last example, you can see that EF figures out which column is the foreign key and where should it point to. How? By using conventions. Having a property of type Person that is named Person with a PersonId property leads EF to conclude that PersonId is a foreign key, and it points to the prima...

In the previous examples a car cannot exist without a person. What if you wanted the person to be optional from the car side? Well, it's kind of easy, knowing how to do one-to-many. Just change the PersonId in Car to be nullable: public class Car { public int CarId { get; set; } public s...

Let's move on to the other scenario, where every person can have multiple cars and every car can have multiple owners (but again, the relationship is bidirectional). This is a many-to-many relationship. The easiest way is to let EF do it's magic using conventions. Just change the model like this: ...

You might want to rename the fields in the join table to be a little more friendly. You can do this by using the usual configuration methods (again, it doesn't matter which side you do the configuration from): public class CarEntityTypeConfiguration : EntityTypeConfiguration<Car> { publi...

I have to admit, I'm not really a fan of letting EF infer the join table wihtout a join entity. You cannot track extra information to a person-car association (let's say the date from which it is valid), because you can't modify the table. Also, the CarId in the join table is part of the primary ke...

HERE Android Premium SDK samples Now available on Github! [https://github.com/heremaps/here-android-sdk-examples][1] HERE iOS Premium SDK samples Now available on Github! [https://github.com/heremaps/here-ios-sdk-examples][1] Please refer to the README.md on how to get started. Note the samples ...