今天学习了scala语言的基础知识,并完成了spark基础实验二的部分内容。
题目1:
import io.StdIn._ object jishu{ def main(args:Array[String]){ var Sn:Float = 0 var n:Float = 1 print("请输入q:") val q = readInt(); while(Sn<q){ Sn += (n+1)/n n += 1 } println("Sn="+Sn) } }
题目2:

case class Point(var x:Double,var y:Double) extends Drawable{ def shift(deltaX:Double,deltaY:Double){x+=deltaX;y+=deltaY} } trait Drawable{ def draw(){println(this.toString)} } // 请完成 Shape 类、Line 类和 Circle 类的定义。 abstract class Shape(var location:Point){//location是Shape的一个可变字段 def moveTo(newLocation:Point){ //默认实现,只是修改位置 location = newLocation } def zoom(scale:Double) } class Line(beginPoint:Point,var endPoint:Point) extends Shape(beginPoint) with Drawable{ override def draw(){ println("line:("+location.x+","+location.y+")--"+"("+endPoint.x+","+endPoint.y+")") } override def moveTo(newLocation:Point){ endPoint.shift(newLocation.x - location.x,newLocation.y - location.y) //直线移动时,先移动另外一个端点 location = newLocation //移动位置 } override def zoom(scale:Double){ val midPoint = Point((endPoint.x + location.x)/2,(endPoint.y + location.y)/2) //求出中点,并按中点进行缩放 location.x = midPoint.x + scale * (location.x - midPoint.x) location.y = midPoint.y + scale * (location.y -midPoint.y) endPoint.x = midPoint.x + scale * (endPoint.x - midPoint.x) endPoint.y = midPoint.y + scale * (endPoint.y -midPoint.y) } } class Circle(center:Point,var radius:Double) extends Shape(center) with Drawable{ override def draw(){//按指定格式重载click println(s"Circle center:(${location.x},${location.y}),R=$radius") } override def zoom(scale:Double){ radius = radius*scale //对圆的缩放只用修改半径 } } object MyDraw{ def main(args: Array[String]) { val p=new Point(10,30) p.draw; val line1 = new Line(Point(0,0),Point(20,20)) line1.draw line1.moveTo(Point(5,5)) //移动到一个新的点 line1.draw line1.zoom(2) //放大两倍 line1.draw val cir= new Circle(Point(10,10),5) cir.draw cir.moveTo(Point(30,20)) cir.draw cir.zoom(0.5) cir.draw } }