forked from golang/hotime
45 lines
853 B
Go
45 lines
853 B
Go
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package stats
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import "math/rand"
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// Sample returns sample from input with replacement or without
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func Sample(input Float64Data, takenum int, replacement bool) ([]float64, error) {
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if input.Len() == 0 {
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return nil, EmptyInput
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}
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length := input.Len()
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if replacement {
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result := Float64Data{}
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rand.Seed(unixnano())
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// In every step, randomly take the num for
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for i := 0; i < takenum; i++ {
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idx := rand.Intn(length)
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result = append(result, input[idx])
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}
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return result, nil
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} else if !replacement && takenum <= length {
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rand.Seed(unixnano())
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// Get permutation of number of indexies
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perm := rand.Perm(length)
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result := Float64Data{}
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// Get element of input by permutated index
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for _, idx := range perm[0:takenum] {
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result = append(result, input[idx])
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}
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return result, nil
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}
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return nil, BoundsErr
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}
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