26 lines
295 B
Text
26 lines
295 B
Text
class StdDev
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declare n
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declare sum
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declare sum2
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def StdDev()
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n = 0
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sum = 0
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sum2 = 0
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end
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def sd(x)
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this.n += 1
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this.sum += x
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this.sum2 += x*x
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return sqrt(sum2/n - sum*sum/n/n)
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end
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end
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testData = {2,4,4,4,5,5,7,9}
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sd = new(StdDev)
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for x in testData
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println sd.sd(x)
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end
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