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DATA _null_; CALL SYMPUT('testVariable','testValueText'); ;RUN; In the example above, %PUT &testVariable; will resolve to testvalueText. You may find the need to format your variable within the SYMPUT() call. DATA _null_; CALL SYMPUT('testDate',COMPRESS(PUT(today(...

Here follows a example of what can be done with nested StackViews, giving the user the impression of a continuous scrolling experience using complex user interface elements or alignments.

A frequent question about StackViews inside Scrollviews comes from ambiguous with/heigh alerts on interface builder. As this answer explained, it is necessary to: Add in the UIScrollView a UIView (the contentScrollView); In this contentScrollView, set top, bottom, left and right margins to 0 Se...

The big gotcha about scrolling is to determine the offset necessary to present (for instance) a Textfield inside a StackView with is inside the ScrollView. If you try to get the position of Textfield.frame.minY can be 0, because the minY frame is only considering the distance between the element an...

LINQ queries do not execute immediately. When you are building the query you are simply storing the query for future execution. Only when you actually request to iterate the query is the query executed (e.g. in a for loop, when calling ToList, Count, Max, Average, First, etc.) This is considered de...

If you want users to upload files to your server you need to do a couple of security checks before you actually move the uploaded file to your web directory. The uploaded data: This array contains user submitted data and is not information about the file itself. While usually this data is generate...

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...

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...

#!/bin/bash deploy=false uglify=false while (( $# > 1 )); do case $1 in --deploy) deploy="$2";; --uglify) uglify="$2";; *) break; esac; shift 2 done $deploy && echo "will deploy... deploy = $deploy" $uglify && echo "will...

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...

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...