28 lines
465 B
Swift
28 lines
465 B
Swift
import Darwin
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class stdDev{
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var n:Double = 0.0
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var sum:Double = 0.0
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var sum2:Double = 0.0
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init(){
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let testData:[Double] = [2,4,4,4,5,5,7,9];
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for x in testData{
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var a:Double = calcSd(x)
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println("value \(Int(x)) SD = \(a)");
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}
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}
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func calcSd(x:Double)->Double{
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n += 1
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sum += x
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sum2 += x*x
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return sqrt( sum2 / n - sum*sum / n / n)
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}
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}
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var aa = stdDev()
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