package Assignment8

import utils.timeVerbose

import scala.collection.parallel.CollectionConverters._

object Ex1 extends App {
  def integrate(a: Double, b: Double, nIntervals: Int, f: (Double => Double)): Double = {
    val dx: Double = (b - a) / nIntervals
    //val y: Double = (1 until nIntervals).map(i => f(i * dx + a)).sum
    //val y: Double = (1 until nIntervals).view.map(i => f(i * dx + a)).sum
    val y: Double = (1 until nIntervals).par.map(i => f(i * dx + a)).sum
    return (2 * y + f(a) + f(b)) * dx / 2
  }

  println(integrate(1, 2, 500, math.sin))

  println(integrate(0, 1, 500, math.sin _ compose math.cos))

  timeVerbose {
    val i = integrate(0, 1, math.pow(20, 6).toInt, math.sin)
  }
}