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Sort an enumeration in either ascending or descending order Synonyms: Sort-Object sort Assuming: $names = @( "Aaron", "Aaron", "Bernie", "Charlie", "Danny" ) Ascending sort is the default: $names | Sort-Object $names | sort Aaron Aa...

You can group an enumeration based on an expression. Synonyms: Group-Object group Examples: $names = @( "Aaron", "Albert", "Alphonse","Bernie", "Charlie", "Danny", "Ernie", "Frank") $names | Group-Object -Prope...

Projecting an enumeration allows you to extract specific members of each object, to extract all the details, or to compute values for each object Synonyms: Select-Object select Selecting a subset of the properties: $dir = dir "C:\MyFolder" $dir | Select-Object Name, FullName, Att...

Class methods present alternate ways to build instances of classes. To illustrate, let's look at an example. Let's suppose we have a relatively simple Person class: class Person(object): def __init__(self, first_name, last_name, age): self.first_name = first_name self.last...

There are two types of using keyword usage, using statement and using directive: using statement: The using keyword ensures that objects that implement the IDisposable interface are properly disposed after usage. There is a separate topic for the using statement using directive The using...

raw_data = {'first_name': ['John', 'Jane', 'Jim'], 'last_name': ['Doe', 'Smith', 'Jones'], 'department': ['Accounting', 'Sales', 'Engineering'],} df = pd.DataFrame(raw_data,columns=raw_data.keys()) df.to_csv('data_file.csv')

This is a very common Exception. It causes your application to stop during the start or execution of your app. In the LogCat you see the message: android.content.ActivityNotFoundException : Unable to find explicit activity class; have you declared this activity in your AndroidManifest.xml? In ...

class Car { public position: number = 0; protected speed: number = 42; move() { this.position += this.speed; } } class SelfDrivingCar extends Car { move() { // start moving around :-) super.move(); super.move(); } } ...

In this example we use the constructor to declare a public property position and a protected property speed in the base class. These properties are called Parameter properties. They let us declare a constructor parameter and a member in one place. One of the best things in TypeScript, is automatic ...

public class Singleton { private static final Singleton INSTANCE = new Singleton(); private Singleton() {} public static Singleton getInstance() { return INSTANCE; } } It can be argued that this example is effectively lazy initialization. Section 12.4.1 of ...

To increment date objects in Javascript, we can usually do this: var checkoutDate = new Date(); // Thu Jul 21 2016 10:05:13 GMT-0400 (EDT) checkoutDate.setDate( checkoutDate.getDate() + 1 ); console.log(checkoutDate); // Fri Jul 22 2016 10:05:13 GMT-0400 (EDT) It is possible to use setD...

To implement an item click listener and/or an item long click listener, you can create an interface in your adapter: public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> { public interface OnItemClickListener { void onItemSeleted(int position, Vi...

countMatches method from org.apache.commons.lang3.StringUtils is typically used to count occurences of a substring or character in a String: import org.apache.commons.lang3.StringUtils; String text = "One fish, two fish, red fish, blue fish"; // count occurrences of a substring Str...

Method references allow predefined static or instance methods that adhere to a compatible functional interface to be passed as arguments instead of an anonymous lambda expression. Assume that we have a model: class Person { private final String name; private final String surname; ...

Start with an iterable which needs to be grouped lst = [("a", 5, 6), ("b", 2, 4), ("a", 2, 5), ("c", 2, 6)] Generate the grouped generator, grouping by the second element in each tuple: def testGroupBy(lst): groups = itertools.groupby(lst, key=lambda...

HTML <p>My shadow always follows me.</p> CSS p { -webkit-filter: drop-shadow(10px 10px 1px green); filter: drop-shadow(10px 10px 1px green); } Result

HTML <div></div> CSS div { width: 100px; height: 100px; background-color: white; -webkit-filter: invert(100%); filter: invert(100%); } Result Turns from white to black.

Carousel components can be instantiated via jQuery with the function $('.carousel').carousel(options), where $('.carousel') is a top-level reference to the specific carousel and options is a Javascript object specifying the carousel's default attributes. The options object allows for multiple prope...

Any is used to check if any element of a collection matches a condition or not. see also: .All, Any and FirstOrDefault: best practice 1. Empty parameter Any: Returns true if the collection has any elements and false if the collection is empty: var numbers = new List<int>(); bool result = ...

using System; using Xamarin.Forms; namespace NavigationApp { public class App : Application { public App() { MainPage = new NavigationPage(new FirstPage()); } } public class FirstPage : ContentPage { Label FirstPage...