forked from golang/hotime
61 lines
1.1 KiB
Go
61 lines
1.1 KiB
Go
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package stats
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import "math"
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// Mean gets the average of a slice of numbers
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func Mean(input Float64Data) (float64, error) {
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if input.Len() == 0 {
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return math.NaN(), EmptyInput
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}
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sum, _ := input.Sum()
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return sum / float64(input.Len()), nil
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}
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// GeometricMean gets the geometric mean for a slice of numbers
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func GeometricMean(input Float64Data) (float64, error) {
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l := input.Len()
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if l == 0 {
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return math.NaN(), EmptyInput
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}
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// Get the product of all the numbers
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var p float64
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for _, n := range input {
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if p == 0 {
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p = n
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} else {
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p *= n
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}
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}
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// Calculate the geometric mean
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return math.Pow(p, 1/float64(l)), nil
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}
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// HarmonicMean gets the harmonic mean for a slice of numbers
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func HarmonicMean(input Float64Data) (float64, error) {
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l := input.Len()
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if l == 0 {
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return math.NaN(), EmptyInput
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}
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// Get the sum of all the numbers reciprocals and return an
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// error for values that cannot be included in harmonic mean
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var p float64
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for _, n := range input {
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if n < 0 {
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return math.NaN(), NegativeErr
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} else if n == 0 {
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return math.NaN(), ZeroErr
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}
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p += (1 / n)
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}
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return float64(l) / p, nil
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}
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