Tutorial by Examples: d

By default, when you are streaming an audio, by exiting the app it will stop, but you can prevent this by turning on the first check box in Background capability page in Xcode. iOS will automatically handle this for you, and you don't need to write any code!

Swift Playgrounds app is a great way to get started coding Swift on the go. To use it: 1- Download Swift Playgrounds for iPad from App Store. 2- Open the app. 3- In the My Playgrounds tab, tap + on the top left corner and then select Blank template. 4- Enter your code. 5- Tap Run My Code to r...

Django's signals are restricted to precise class signatures upon registration, and thus subclassed models are not immediately registered onto the same signal. Take this model and signal for example class Event(models.Model): user = models.ForeignKey(User) class StatusChange(Event): ...

Creating a Scala function that receives an python RDD is easy. What you need to build is a function that get a JavaRDD[Any] import org.apache.spark.api.java.JavaRDD def doSomethingByPythonRDD(rdd :JavaRDD[Any]) = { //do something rdd.map { x => ??? } }

This part of development you should serialize the python RDD to the JVM. This process uses the main development of Spark to call the jar function. from pyspark.serializers import PickleSerializer, AutoBatchedSerializer rdd = sc.parallelize(range(10000)) reserialized_rdd = rdd._reserialize(Aut...

Sometimes, the straight forward loop cannot be entirely contained within the loop body. This is because, the loop needs to be primed by some statements B. Then, the iteration begins with some statements A, which are then followed by B again before looping. do_B(); while (condition) { do_A(); ...

Using many ECHO commands to create a batch file: ( echo echo hi, this is the date today echo date /T echo echo created on %DATE% echo pause >nul )>hi.bat The command interpreter treats the whole section in parenthesis as a single command, then saves all the output to hi.bat. ...

Ant provides some built-in properties Property NameValuebasedirthe absolute path of the project's basedirant.filethe absolute path of the buildfile.ant.versionthe version of Antant.project.default-targetthe name of the currently executing project's default targetant.project.namename of the projecta...

There are two ways to define models in sequelize; with sequelize.define(...), or sequelize.import(...). Both functions return a sequelize model object. 1. sequelize.define(modelName, attributes, [options]) This is the way to go if you'd like to define all your models in one file, or if you want to...

One of the major use case when a developer needs to take mutability into account is when passing arguments to a function. This is very important, because this will determine the ability for the function to modify objects that doesn't belong to its scope, or in other words if the function has side ef...

First, complete the installation and setup to connect your app to Firebase. Then from anywhere in your class, you can write: // Write a message to the database FirebaseDatabase database = FirebaseDatabase.getInstance(); DatabaseReference myRef = database.getReference("message"); myRe...

Gradle (All Versions) This method works for all versions of gradle Add the buildscript code at the beginning of your build.gradle file. buildscript { repositories { maven { url "https://plugins.gradle.org/m2/" } } dependencies { classpath "org.example...

Gradle (All Versions) When adding multiple third party plugins you do not need to separate them into different instances of the buildscript(All) or plugin(2.1+) code, new plug ins can be added alongside pre-existing plugins. buildscript { repositories { maven { url "https://plu...

A deque is a double-ended queue. class Deque: def __init__(self): self.items = [] def isEmpty(self): return self.items == [] def addFront(self, item): self.items.append(item) def addRear(self, item): self.items.insert(0,item) def removeFront(self): return self....

When using d3.request() or one of the convenience constructors (d3.json, d3.csv, d3.tsv, d3.html and d3.xml) there are many sources for error. There may be problems with the issued request or its response due to network errors, or the parsing might fail if the content is not well-formed. Within the...

Decryption Code public static string Decrypt(string cipherText) { if (cipherText == null) return null; byte[] cipherBytes = Convert.FromBase64String(cipherText); using (Aes encryptor = Aes.Create()) { Rfc2898DeriveBytes pdb = ...

We can use command uname with various options to get complete details of running kernel. uname -a Linux df1-ws-5084 4.4.0-64-generic #85-Ubuntu SMP Mon Feb 20 11:50:30 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux As per man page here few more options Usage: uname [OPTION]... Print certain system inf...

Let's initially understand basic types of custom validators: Inline Validator Standalone Validator Inline Validator: It is the type of the validator we create inside the class which is basically a method we define just like other methods but with extra parameters which is passed in by Yii2. ...

While designing a form, you might like to group a few input fields into a group to help organise the form layout. This can be done by using the tag . Here is an example for using it. For each fieldset, you can set a legend for the set using the tag LEGEND TEXT Example <form> <fieldset...

This is a jumbotron with a title, a content and a button. Code <div class="jumbotron"> <h1>Title text</h1> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec tortor ipsum, convallis sit.</p> <p><a class="btn btn-default&...