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The bitwise NOT (~) performs a NOT operation on each bit in a value. Syntax: ~expression Returns: a Number. Description The truth table for the NOT operation is: aNOT a01101337 (base 10) = 0000010100111001 (base 2) ~1337 (base 10) = 1111101011000110 (base 2) = -1338 (base 10) A bit...

The logical NOT (!) operator performs logical negation on an expression. Syntax: !expression Returns: a Boolean. Description The logical NOT (!) operator performs logical negation on an expression. Boolean values simply get inverted: !true === false and !false === true. Non-boolean val...

In Oracle a DATE data type does not have a format; when Oracle sends a DATE to the client program (SQL/Plus, SQL/Developer, Toad, Java, Python, etc) it will send 7- or 8- bytes which represent the date. A DATE which is not stored in a table (i.e. generated by SYSDATE and having "type 13" ...

When Oracle implicitly converts from a DATE to a string or vice-versa (or when TO_CHAR() or TO_DATE() are explicitly called without a format model) the NLS_DATE_FORMAT session parameter will be used as the format model in the conversion. If the literal does not match the format model then an excepti...

Unlike Big-O notation, which represents only upper bound of the running time for some algorithm, Big-Theta is a tight bound; both upper and lower bound. Tight bound is more precise, but also more difficult to compute. The Big-Theta notation is symmetric: f(x) = Ө(g(x)) <=> g(x) = Ө(f(x)) An ...

Similar to the built-in function zip(), itertools.zip_longest will continue iterating beyond the end of the shorter of two iterables. from itertools import zip_longest a = [i for i in range(5)] # Length is 5 b = ['a', 'b', 'c', 'd', 'e', 'f', 'g'] # Length is 7 for i in zip_longest(a, b): x...

Visual Basic has Left, Right, and Mid functions that returns characters from the Left, Right, and Middle of a string. These methods does not exist in C#, but can be implemented with Substring(). They can be implemented as an extension methods like the following: public static class StringExtens...

The view-model is the "VM" in MVVM. This is a class that acts as a go-between, exposes the model(s) to the user interface (view), and handling requests from the view, such as commands raised by button clicks. Here is a basic view-model: public class CustomerEditViewModel { /// <s...

The model is the first "M" in MVVM. The model is usually a class containing the data that you want to expose via some kind of user interface. Here is a very simple model class exposing a couple of properties:- public class Customer : INotifyPropertyChanged { private string _forenam...

The View is the "V" in MVVM. This is your user interface. You can use the Visual Studio drag-and-drop designer, but most developers eventually end up coding the raw XAML - an experience similar to writing HTML. Here is the XAML of a simple view to allow editing of a Customer model. Rather...

return http://www.example.com/skin/frontend/{interface}/{theme}/images/my-image.jpg

It is possible to limit the tests executed by manage.py test by specifying which modules should be discovered by the test runner: # Run only tests for the app names "app1" $ python manage.py test app1 # If you split the tests file into a module with several tests files for an app $ p...

<PROJECT_ROOT>\app\build.gradle is specific for app module. <PROJECT_ROOT>\build.gradle is a "Top-level build file" where you can add configuration options common to all sub-projects/modules. If you use another module in your project, as a local library you would have another...

/** * The first line in the build configuration applies the Android plugin for * Gradle to this build and makes the android {} block available to specify * Android-specific build options. */ apply plugin: 'com.android.application' /** * The android {} block is where you configure all...

The return statement can be a useful way to create output for a function. The return statement is especially useful if you do not know in which context the function will be used yet. //An example function that will take a string as input and return //the first character of the string. function...

We will see how to center content based on the height of a near element. Compatibility: IE8+, all other modern browsers. HTML <div class="content"> <div class="position-container"> <div class="thumb"> <img src="http://lorempix...

people := map[string]int{ "john": 30, "jane": 29, "mark": 11, } for _, value := range people { fmt.Println("Age:", value) } Note that when iterating over a map with a range loop, the iteration order is not specified and is not guaranteed to...

From within a generator function, the control can be delegated to another generator function using yield*. function* g1() { yield 2; yield 3; yield 4; } function* g2() { yield 1; yield* g1(); yield 5; } var it = g2(); console.log(it.next()); // 1 console.log(it.next())...

In the following examples, we'll be using the following samples: List<Product> Products = new List<Product>() { new Product() { ProductId = 1, Name = "Book nr 1", Price = 25 }, new Product() { ProductId = 2, Name = "Book nr 2&quot...

A common question is "I have a value of IO a, but I want to do something to that a value: how do I get access to it?" How can one operate on data that comes from the outside world (for example, incrementing a number typed by the user)? The point is that if you use a pure function on data ...