32 lines
586 B
Go
32 lines
586 B
Go
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package stats
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import "math"
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// Entropy provides calculation of the entropy
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func Entropy(input Float64Data) (float64, error) {
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input, err := normalize(input)
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if err != nil {
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return math.NaN(), err
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}
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var result float64
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for i := 0; i < input.Len(); i++ {
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v := input.Get(i)
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if v == 0 {
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continue
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}
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result += (v * math.Log(v))
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}
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return -result, nil
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}
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func normalize(input Float64Data) (Float64Data, error) {
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sum, err := input.Sum()
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if err != nil {
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return Float64Data{}, err
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}
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for i := 0; i < input.Len(); i++ {
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input[i] = input[i] / sum
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}
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return input, nil
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}
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