打印不显示在控制台(swift)

时间:2017-10-19 07:50:35

标签: swift printf

我的代码无法在控制台中打印。我尝试了一些方法,但没有任何工作。下面的代码是代码的完整版本,可能导致打印未显示在控制台中的原因。请帮我识别这个小问题。我尝试使用尽可能多的方法来调试此问题,但无济于事。

这是我的代码:

import Foundation

// Function to calculate the arithmetic mean

func arithmeticMean(array: [Double]) -> Double {
    var total: Double = 0
    for number in array {
        total += number
    }
    return total / Double(array.count)
}

// Function to calculate the standard deviation

func standardDeviation(array: [Double]) -> Double
{
    let length = Double(array.count)
    let avg = array.reduce(0, {$0 + $1}) / length
    let sumOfSquaredAvgDiff = array.map { pow($0 - avg, 2.0)}.reduce(0, {$0 + $1})
    return sqrt(sumOfSquaredAvgDiff / length)
}

// Function to extract some range from an array

func subArray<T>(array: [T], s: Int, e: Int) -> [T] {
    if e > array.count {
        return []
    }
    return Array(array[s..<min(e, array.count)])
}

// Smooth z-score thresholding filter

func ThresholdingAlgo(y: [Double],lag: Int,threshold: Double,influence: Double) -> ([Int],[Double],[Double]) {

    // Create arrays
    var signals   = Array(repeating: 0, count: y.count)
    var filteredY = Array(repeating: 0.0, count: y.count)
    var avgFilter = Array(repeating: 0.0, count: y.count)
    var stdFilter = Array(repeating: 0.0, count: y.count)

    // Initialise variables
    for i in 0...lag-1 {
        signals[i] = 0
        filteredY[i] = y[i]
    }

    // Start filter
    avgFilter[lag-1] = arithmeticMean(array: subArray(array: y, s: 0, e: lag-1))
    stdFilter[lag-1] = standardDeviation(array: subArray(array: y, s: 0, e: lag-1))

    for i in lag...y.count-1 {
        if abs(y[i] - avgFilter[i-1]) > threshold*stdFilter[i-1] {
            if y[i] > avgFilter[i-1] {
                signals[i] = 1      // Positive signal
            } else {
                // Negative signals are turned off for this application
                signals[i] = -1       // Negative signal
            }
            filteredY[i] = influence*y[i] + (1-influence)*filteredY[i-1]
        } else {
            signals[i] = 0          // No signal
            filteredY[i] = y[i]
        }
        // Adjust the filters
        avgFilter[i] = arithmeticMean(array: subArray(array: filteredY, s: i-lag, e: i))
        stdFilter[i] = standardDeviation(array: subArray(array: filteredY, s: i-lag, e: i))
    }
    return (signals,avgFilter,stdFilter)
}


func viewDidLoad()
{

// Demo

let samples = [0.01, -0.02, -0.02, 0.01, -0.01, -0.01, 0.00, 0.10, 0.31,
               -0.10, -0.73, -0.68, 0.21, 1.22, 0.67, -0.59, -1.04, 0.06, 0.42, 0.07,
               0.03, -0.18, 0.11, -0.06, -0.02, 0.16, 0.21, 0.03, -0.68, -0.89, 0.18,
               1.31, 0.66, 0.07, -1.62, -0.16, 0.67, 0.19, -0.42, 0.23, -0.05, -0.01,
               0.03, 0.06, 0.27, 0.15, -0.50, -1.18, 0.11, 1.30, 0.93, 0.16, -1.32,
               -0.10, 0.55, 0.23, -0.03, -0.23, 0.16, -0.04, 0.01, 0.12, 0.35, -0.38,
               -1.11, 0.07, 1.46, 0.61, -0.68, -1.16, 0.29, 0.54, -0.05, 0.02, -0.01,
               0.12, 0.23, 0.29, -0.75, -0.95, 0.11, 1.51, 0.70, -0.30, -1.48, 0.13,
               0.50, 0.18, -0.06, -0.01, -0.02, 0.03, -0.02, 0.06, 0.03, 0.03, 0.02,
               -0.01, 0.01, 0.02, 0.01]

// Run filter

let (signals,avgFilter,stdFilter) = ThresholdingAlgo(y: samples, lag: 10, threshold: 3, influence: 0.2)

// Print output to console
print("\nOutput: \n ")

    for i in 0...signals.count - 1
    {
        print("Data point \(i)\t\t sample: \(samples[i]) \t signal: \(signals[i])\n")
    }

    // Raw data for creating a plot in Excel
    print("\n \n Raw data for creating a plot in Excel: \n ")
    for i in 0...signals.count - 1
    {
        print("\(i+1)\t\(samples[i])\t\(signals[i])\t\(avgFilter[i])\t\(stdFilter[i])\n")
    }
}

非常感谢您的帮助!我已经添加了整个代码,因此这可能有助于调试问题。

2 个答案:

答案 0 :(得分:1)

好吧也许我找到了你的问题。函数viewDidLoad不在任何类中,并且它不会覆盖任何委托方法。这意味着当视图出现时不会自动调用它。

实施例

class ViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad() // the view did load gets called when view appears
    // Do any additional setup after loading the view, typically from a nib.
}
}

在这种情况下,我们的类在显示视图时加载,但是您的函数viewDidLoad不在任何类中。

答案 1 :(得分:0)

信号数组可能是空的,因此循环不会被执行。 也许你想把“samples.cout-1”而不是“信号”?