scala book

A function is a set of statements that perform a task together. You can put your code in a separate function. How to divide your code between different functions, but logically, partitioning is usually to allow each function to perform a specific task. Scala has functions and methods, and our terminology says that the methods and functions are interchangeable in small differences. The Scala approach is to h

1. Download1.1Scala DownloadsWindows Edition: http://www.scala-lang.org/download/Linux version: http://www.scala-lang.org/download/2.11.8.htmlPull to the bottom:1.2ScalaIDE Downloads: http://scala-ide.org/download/sdk.htmlinstall Scala under 2.WindowsEnvironment: windows10+jdk1.7+scala2.11.82.1 InstallationHere, change the installation location:Done2.2 Test whether the installation was successfulFirst, set

Classes (Class)A class is a template for an object that, by constructing a class, can declare a series of objects of the same structure using the New keyword. One source file for Scala can contain more than one public class. Declaring the person class: Class person{ var name:string = _ Val Age = 10 Private[this] val gender = "Male" } Description The Name field is assigned the value "_" "_", which is a placeholder. Indicates that name is declared as St

About ScalaScala is a "stretched language", which can be changed and grown with the needs of the user. Scala can be used in a wide range of programming tasks, as small as scripts to build systems. Scala runs on the standard Java platform and can interact seamlessly with all Java libraries. It adds object-oriented and functional programming concepts to statically typed languages .

http://blog.csdn.net/lovehuangjiaju/article/details/47009607 The main contents of this section 1 class definitions, creating objects2 Main constructor3 Auxiliary constructor class definition, creating object Use keyword class to define class person { //class member must initialize, otherwise error //This is defined as a public member var name:string=null }1 2 3 4 5 6 1 2 3 4 5 6 The person class generates a Person.class file after compilingUsing the javap-prviate Person command to view t

Scala entry-Eclipse Development Environment setup Due to the need for deep learning, I recently started to learn Scala, an artistic programming language. Scala: a java-like programming. Integrates the features of Object-Oriented (Oriented) programming and Functional (Functional programming) programming, which facilitates the development of multi-core concurrency

To use Spark, learn Scala first.Reference Tutorial: Http://meetfp.com/zh/scala-basicOnline compilation: Http://meetfp.com/tryoutOther information: HTTP://SCALACHINA.COM/NODE/16 http://blog.csdn.net/mapdigit/article/details/21878083Characteristics: Scala is a purely object-oriented language, all objects: Unify primitive types and classes, and unify functi

, y)) x:: Merge (XS1, ys) els E y:: Merge (XS, ys1)} val n = xs.length/ 2 if (n = = 0 ) xs e LSE {val (ys, ZS) = xs splitat n merge (Msort (less) (YS), Msort (less) (ZS )) } }} Quick SortQuick ordering of prescriptive styles: defQsort (Xs:array[int]): Unit = {defSwap (I:int, j:int): Unit = {Valt = xs (i); XS (i) = XS (j); XS (j) = T}defSort1 (L:int, r:int): Unit = {ValPivot = XS ((l+r)/2)vari = l;varj = R while(I while(XS (i) 1 while(XS (j) > Pivot)

} Object donothingaction extends undoableaction("Do Nothing" ) { Override defUndo () {}Override defRedo () {}}//Open and save features not yet implementedValAction = Map ("Open"Donothingaction,"Save"Donothingaction, ...)The Donothingaction object can be shared by all places where this default behavior is requiredExamples of mixed traitsSometimes you can mix things like debugger or logging to build objects to help debug objects so that the object instance you build has a method like log:trait

=> Int)(a: Int, b: Int): Int = if0else1, b)This makes the function writing more concise.In general, a multi-parameter function is defined as def f(args1)...(argsn) = E ,When n > 1 o'clock, equal to def f(args1)...(args n-1) = {def g(argsn) = E; g} or def f(args1)...(args n-1) = (argsn => E) .If you repeat this process n times, get it def f = (args1 => (args2 => ... (argsn => E) ) ) .This function definition is called curry (currying).reprint Please indicate the author Jason Ding and its prove

When I was learning computer programming, I think most people would experience the same as the author, school for us to pick a language, mostly C or Java, first the basic data type, then the program control statements, conditional judgment, cycle, etc., the book will teach us how to define a function, will say that the program is a piece of instructions, Tell the computer how to operate. We also see how to define a recursive function to compute the fa

In the first article in this series, "thinking by using recursion," the authors do not introduce Scala's syntax first, for two reasons: one is because too much of the grammatical details distract the reader, ignoring the basic concept, the basic idea; and the second is that Scala The syntax is very concise, and programmers with other language programming experience can easily read Scala code. Now we're goin

Install Scala and Spark in CentOS 1. Install Scala Scala runs on the Java Virtual Machine (JVM). Therefore, before installing Scala, you must first install Java in linux. You can go to my article http://blog.csdn.net/xqclll/article/details/54256713to continue without installing the SDK. Download the

checksumaccumulator { private var sum = 0 = { + = b } = { return ~ (sum 0xFF) + 1 }}Any parameters passed to the method can be used inside the method. An important feature of the method parameters in Scala is that they are all Val, not var. If you want to reassign a parameter to a method, the result is a compilation failure:Scala> def Add (b:byte): Unit = { | // compile however, because B is Val | sum + = b| } a membe

Description, since Spark was written in Scala. Therefore, it is best to use Scala whether you are looking at the source code or writing spark-related codes. Then, as a programmer, the first thing to do is to sharpen the sword in hand. That's creating a code environment for writing Scala. Here because I am personally familiar with eclipse (although I think he is a

Background Notes Recent research spark need Scala to prepare a Scala environment for documenting the configuration notes.The Scala language is based on the Java language, so you have to install the JDK first. Experimental Environment: Win7 under VMware Virtual machine operating system: CentOS 6.5 x64 java:jdk-8u161-linux-x64.tar.gz scala:scala-2.12.4.tgz Install

1.lazyLazy calculationLazy evaluation is particularly useful in functional programming languages. When a delay evaluation is used, the expression is not evaluated immediately after it is bound to the variable, but is evaluated when the value is taken. In addition to the performance gains, the most important benefit of lazy computing is that it can construct an infinite data type.In Scala, the Lazy keyword is used to define the lazy variable, and the l