Scala Aufgabe 5

aufgabe5.scala

package aufgabe5

class Matrix[T](val xDim:Int, val yDim:Int, protected val data:Array[T])(implicit num : Numeric[T], m : Manifest[T]) {
  val numeric = num
  val manifest = m

  def apply(x:Int, y:Int):T =
    if (x < 0 || x >= xDim || y < 0 || y >= yDim)
      numeric.zero
    else
      data(x+xDim*y)

  def +(other:Matrix[T])= {
    require (xDim == other.xDim && yDim == other.yDim)
    new Matrix(xDim, yDim, data.zip(other.data).map((p) => num.plus(p._1,p._2)))
  }
  def -(other:Matrix[T])= {
    require (xDim == other.xDim && yDim == other.yDim)
    new Matrix(xDim, yDim, data.zip(other.data).map((p) => num.plus(p._1,p._2)))
  }

  override def toString =
    "Matrix[%s](%s)" format (manifest, data.grouped(xDim).map( "(%s)" format _.mkString(", ") ).mkString(", "))
}

object Matrix {
  // Matrix(dim, *values)
  def apply[T](dim:Int)(values:T*)(implicit num : Numeric[T], m : Manifest[T]) =
    new Matrix(dim, dim, values.toIndexedSeq.padTo(dim*dim, num.zero).toArray) // true?

  // Matrix(dim, func)
  def apply[T](dim:Int, func:(Int,Int)=>T)(implicit num : Numeric[T], m : Manifest[T]):Matrix[T] =
    new Matrix(dim, dim, Array.tabulate(dim,dim)(func).flatten)

  // Matrix( array(array()) )
  def apply[T](values:Array[Array[T]])(implicit num : Numeric[T], m : Manifest[T]):Matrix[T]=
    new Matrix(values.size, values.size, values.flatten)
}


// go out of my way

object Application {
  def main(args:Array[String]) {

    val mat01 = new Matrix(2,2,Array(1,2,3,4))
    val mat02 = new Matrix(2,2,Array(4,3,2,1))
    println(mat01)
    println(mat02)

    // println(Matrix(1)(true)) // <- compiliert nich

    println(Matrix(3)(1, 2, 3))
    println(Matrix(3)(1.0, 2, 3))
    println(Matrix(2)(BigDecimal(2)))

    println()

    val mat1 = Matrix(5, (x, y) => if (x == y) 1 else 0)
    val mat2 = Matrix(Array(Array(3, 2, 1), Array(0, 1, 0), Array(0, 0, 3)))
    val mat3 = Matrix(1)(1.01)

    println(mat1)
    println(mat2)
    println(mat3)

    println()

    println(mat1(0, 0))
    println(mat1(4, 0))
    println(mat1(4, 4))
    println(mat1(5, 5))

    println()

    println(mat1 + mat1)
    println(Matrix(3)(1, 2, 3) + mat2)
    println(Matrix(3)(1, 2, 3) + mat2 + Matrix(3, (i, j) => i + j))
    println(mat3 + Matrix(1)(0))
  }
}