cuckookernel · August 3, 2019 17:57
diff --git a/extend_array b/extend_array

 extension Array where Element == Double {

  func mean() -> Double {
    if self.count == 0 { return Double.nan } 
    
    var ret = 0.0
    
    for  x in ret  {
      ret += x 
    }
    
    return ret / self.count
    
  }
 }

	extension Array where Element == Double {

	func mean() -> Double {
	if self.count == 0 { return Double.nan }

	var ret = 0.0

	for x in ret {
	ret += x
	}

	return ret / self.count

	}
	}