scala matrix

gistfile1.scala

trait MatrixBinOps[T] {
  def +(that: Matrix[T])(implicit ev: Vector[Numeric[T]]): Matrix[T]
  def -(that: Matrix[T])(implicit ev: Vector[Numeric[T]]): Matrix[T]
  def *(that: Matrix[T])(implicit ev: Vector[Numeric[T]]): Matrix[T]
}

trait Matrix[T] {
  // def zeros(length: Int)(implicit ev: Numeric[T]): Vector[T]
  // def toString(): String
}


object Matrix {
  def apply[T](args: Vector[T]*): Matrix[T] = new MatrixImpl[T](args.toList)

  private class MatrixImpl[@specialized(Double, Int, Float, Long)T](val _data: List[Vector[T]])
    extends Matrix[T]
    with MatrixBinOps[T] {
    def +(that: Matrix[T])(implicit em: Vector[Numeric[T]]): Matrix[T] = new MatrixImpl[T](_data.zip(that).map(elem => elem._1 + elem._2))
    def -(that: Matrix[T])(implicit em: Numeric[T]): Matrix[T] = new MatrixImpl[T](_data.zip(that).map(elem => elem._1 - elem._2))
    def *(that: Matrix[T])(implicit em: Numeric[T]): Matrix[T] = new MatrixImpl[T](_data.zip(that).map(elem => elem._1 * elem._2))

    // def fill(length: Int, value: T): Vector[T] = new VectorImpl[T](List.fill[T](length)(value))

    // def zeros(length: Int)(implicit ev: Numeric[T]): Vector[T] = fill(length, ev.zero)
    def toList(): List[Vector[T]] = _data

    // override def toString(): String = "Vector(" + _data.mkString(" , ") + ")"
  }

  implicit def MatrixToList[T](m: Matrix[T]): List[Vector[T]] = m.toList
}