swift手记-2

//

//  ViewController.swift

//  learn2

//

//  Created by myhaspl on 16/1/19.

//  Copyright (c) 2016年 myhaspl. All rights reserved.

///Volumes/myhaspl/book/swift算法/src/2/learn2/learn2/Base.lproj/Main.storyboard

import Cocoa

class ViewController: NSViewController {

    override func viewDidLoad() {

        super.viewDidLoad()

        // Do any additional setup after loading the view.

    }

    override var representedObject: AnyObject? {

        didSet {

        // Update the view, if already loaded.

        }

    }

    private func compute(n:Int)->String{

        //计算阶乘，如果计算的参数大于30，则进行近似计算

        var result:Double = 1

        if n<30 {

            for i:Int in 1 ... n {

                result = result * Double(i)

            }

        }

        else {

            var result1:Double = sqrt(2 * M_PI * Double(n))

            var result2 :Double = pow(Double(n)/M_E ,Double(n))

            result = result1 * result2

        }

        return "结果"+String(stringInterpolationSegment:result)

    }

    @IBOutlet weak var Number: NSTextField!

    @IBOutlet weak var ComputeResult: NSTextField!

    @IBAction func jqCom(sender: AnyObject) {

        if let n:Int=self.Number.stringValue.toInt() {

           self.ComputeResult.stringValue=compute(n)

        }

    }

    

}