func CloseCenter(p gopark.Vector, centers []gopark.Vector) int {
minDist := p.EulaDistance(centers[0])
minIndex := 0
for i := 1; i < len(centers); i++ {
dist := p.EulaDistance(centers[i])
if dist < minDist {
minDist = dist
minIndex = i
}
}
return minIndex
}
