package main

import (
	"fmt"
	"math"
)

func uniq(list []float64) []float64 {
	unique_set := map[float64]int{}
	i := 0
	nan := false
	for _, x := range list {
		if _, exists := unique_set[x]; exists {
			continue
		}
		if math.IsNaN(x) {
			if nan {
				continue
			} else {
				nan = true
			}
		}
		unique_set[x] = i
		i++
	}
	result := make([]float64, len(unique_set))
	for x, i := range unique_set {
		result[i] = x
	}
	return result
}

func main() {
	fmt.Println(uniq([]float64{1, 2, math.NaN(), 2, math.NaN(), 4})) // Prints [1 2 NaN 4]
}