code: func (ps PointSet) DistanceFrom(point *Point) (float64, int) {
  	dist := math.Inf(1)
  	index := 0
  
  	for i := range ps {
  		if d := ps[i].SquaredDistanceFrom(point); d < dist {
  			dist = d
  			index = i
  		}
  	}
  
  	return math.Sqrt(dist), index
  }
docs: // DistanceFrom returns the minimum euclidean distance from the point set.