scalaでマンデルブロ

M.scala

object M{val W=200;val H=80;def m(v:Float,a:Float,b:Float,c:Float,d:Float)=c+(d-c)*((v-a)/(b-a));def r(a:Float,b:Float,x:Float,y:Float,c:Int):Int=if(Math.abs(x*x+y*y)>2) c else if(c>999) 0 else r(a,b,x*x-y*y+a,2*x*y+b,c+1);def c(a:Float,b:Float)=r(a,b,0,0,0);def main(a:Array[String])=for(j<-(0 to H).map(m(_,0,H,-2,2))){for(i<-(0 to W).map(m(_,0,W,-2,2))){print(if(c(i,j)==0) 2 else 9)};println()}}

Main.scala

object Main {
  val N = 100
  val W_SIZE = 200
  val H_SIZE = 80
  val X_MIN = -1.75f
  val X_MAX = 1.25f
  val Y_MIN = -1.5f
  val Y_MAX = 1.5f

  def m(v: Float, s1: Float, e1: Float, s2: Float, e2: Float) = s2 + (e2 - s2) * ((v - s1) / (e1 - s1))

  def r(a: Float, b: Float, x: Float, y: Float, c: Int): Int = if (scala.math.abs(x * x + y * y) > 2) c else if (c >= N) 0 else r(a, b, x * x - y * y + a, 2 * x * y + b, c + 1)

  def calc(a: Float, b: Float) = r(a, b, 0, 0, 0)

  def main(args: Array[String]) = {
    (0 until H_SIZE).map(m(_, 0, H_SIZE, Y_MIN, Y_MAX)).foreach(j => {
      (0 until W_SIZE).map(m(_, 0, W_SIZE, X_MIN, X_MAX)).foreach(i => {
        print(if (calc(i, j) == 0) 2 else 9)
      })
      println();
    })
  }
}