Tutorial by Examples: d

The following example is high level coverage of the key concepts and basic skeletal setup:- Collects credentials from the user (Usually from a login screen you've created) Authenticates the credentials with the server (stores custom authentication) Stores the credentials on the device Exte...

A frequent reason why your read operation may not work is because your security rules reject the operation, for example because you're not authenticated (by default a database can only be accessed by an authenticated user). You can see these security rule violations in the JavaScript console of you...

You can define your own behaviour by adding -callback directives in your module. For example, if modules implementing your behaviour need to have a foo function that takes an integer and returns an atom: -module(my_behaviour). -callback foo(integer()) -> atom(). If you use this behaviour in...

It's easiest to show a binary search on numbers using pseudo-code int array[1000] = { sorted list of numbers }; int N = 100; // number of entries in search space; int high, low, mid; // our temporaries int x; // value to search for low = 0; high = N -1; while(low < high) { mid = (...

Cannot add Integer and Real* - 5 + 1.0; stdIn:1.2-10.4 Error: operator and operand don't agree [overload conflict] operator domain: [+ ty] * [+ ty] operand: [+ ty] * real in expression: 5 + 1.0

JavaFX has a binding API, which provides ways of binding one property to the other. This means that whenever one property's value is changed, the value of the bound property is updated automatically. An example of simple binding: SimpleIntegerProperty first =new SimpleIntegerProperty(5); //create a...

Installation Additional dependencies are required for Redis support. Install both Celery and the dependencies in one go using the celery[redis] bundle: $ pip install -U celery[redis] Configuration Configure the location of your Redis database: BROKER_URL = 'redis://localhost:6379/0' The UR...

Case 1: While using in the place of method arguments. If a method requires an object of wrapper class as argument.Then interchangeably the argument can be passed a variable of the respective primitive type and vice versa. Example: int i; Integer j; void ex_method(Integer i)//Is a valid statem...

You can access the command line arguments passed to your program using the std::env::args() function. This returns an Args iterator which you can loop over or collect into a Vec. Iterating Through Arguments use std::env; fn main() { for argument in env::args() { if argument == &qu...

Jersey (2) uses HK2 as its dependency injection (DI) system. We can use other injection systems, but its infrastructure is built with HK2, and allows us to also use it within our applications. Setting up simple dependency injection with Jersey takes just a few lines of code. Let say for example we ...

This is same as reading a manual for a command: man /path/to/man/file

A TabbedPage is similar to a NavigationPage in that it allows for and manages simple navigation between several child Page objects. The difference is that generally speaking, each platform displays some sort of bar at the top or bottom of the screen that displays most, if not all, of the availabl...

Spring Boot is a bootstrapping framework for Spring applications. It has seamless support for integrating with Jersey also. One of the advantages of this (from the perspective of a Jersey user), is that you have access to Spring's vast ecosystem. To get started, create a new standalone (non-wepapp)...

Why annotations? Generally we use annotation to facilitate the development and to make the code more clear and clean. What are annotations? Java 5 annotations provide standardization of metadata in a general goal. This metadata associated with Java features can be exploited in the compilation or ...

Create managed bean To create a manage bean you need the annotation @ManagedBean for example: @ManagedBean public class Example {} You need the package: import javax.faces.bean.ManagedBean; Managed bean Scope We use annotations to define the scope in which the bean will be stored. There...

This example uses Angular 2.0.0 Final Release registration-form.component.ts import { FormGroup, FormControl, FormBuilder, Validators } from '@angular/forms'; @Component({ templateUrl: "./registration-form.html" }) export class ExampleComponent { ...

To add a code block, surround it with #+BEGIN_SRC language and #+END_SRC. language should correspond to the major mode for the language in question, e.g. the major mode for Emacs Lisp is emacs-lisp-mode, so write #+BEGIN_SRC emacs-lisp. #+BEGIN_SRC emacs-lisp (defun hello-world () (interactive)...

The pandas.DataFrame.apply() method is used to apply a given function to an entire DataFrame --- for example, computing the square root of every entry of a given DataFrame or summing across each row of a DataFrame to return a Series. The below is a basic example of usage of this function: # create...

The iv is prefixed to the encrypted data aesCBC128Encrypt will create a random IV and prefixed to the encrypted code. aesCBC128Decrypt will use the prefixed IV during decryption. Inputs are the data and key are Data objects. If an encoded form such as Base64 if required convert to and/or from in ...

A very handy way to subset Time Series is to use partial string indexing. It permits to select range of dates with a clear syntax. Getting Data We are using the dataset in the Creating Time Series example Displaying head and tail to see the boundaries se.head(2).append(se.tail(2)) # 2016-09-2...