本文共 1134 字,大约阅读时间需要 3 分钟。
Array | List,Set | Map | Tuple1…20 | |
---|---|---|---|---|
创建容器 | Array(1,2,3) | List(1,2,3) / Array(1,2,3).toList | Map(“k1”->“1”,“k2”->“2”) | scala.Tuple3(1,2,3)/ (1,2,3) |
取出元素 | arr(0), arr(1) | list(0),list(1) | map(“k1”) | tup._1, tup._2 |
常用函数 | size, sum,min, max,toList, flatMap | sortBy,reverse,toMap,flatMap,groupBy,reduce | map,mapValues,groupBy,filter |
函数
//for循环for(i<-1 to 9){ for(j <-1 to 9){ if(i>=j){ printf("%d * %d = %d \t", j,i,(j*i)) } } println()}import scala.util.control.Breaks._for(i<- 1 to 9; j<- 1 to 9){ if(i>=j){ printf("%d * %d = %d \t", j,i,(j*i)) }else { if(j>i) {println() ; return} }}for(i<-"hello"){ println(i)}
//while循环var x=5while( x>0){ println(x) x-=1}
//定义方法 def thread(f: () => Unit) = { new Thread() { override def run() = { f() } }.start() } //启动线程1 : 死循环打印a def f = { while (true) println("a") Thread.sleep(100) } thread(f _) //启动线程2: 打印一个hello thread(() => println("hello"))
//求解: 直线方程def f( x1:Int,y1:Int, x2:Int, y2:Int ):Int=>Int = { k=(y2-y1)/(x2-x1) b=y1-k*x1 def fun(x:Int)={ k*x+b } fun _}f(1,2,3,4)(5)