if (numberList.Any())

             {

                 exEntity.MinValue = numberList.First().NumberValue.ToString();

                 exEntity.MaxValue = numberList.Last().NumberValue.ToString();

                 exEntity.AvgValue = Math.Round((decimal)numberList.Average(p => p.NumberValue), ).ToString();

                 //标准差

                 if (numberList.Count > )

                 {

                     double sumOfSquare = ; //平方总和

                     foreach (var item in numberList)

                     {

                         double numberValue = double.Parse(item.NumberValue.ToString());

                         sumOfSquare += Math.Pow((numberValue - double.Parse(exEntity.AvgValue)), );

                     }

                     double stdDeviation = Math.Sqrt(sumOfSquare / (numberList.Count - ));

                     stdDeviation = Math.Round(stdDeviation, );

                     exEntity.StdDeviation = stdDeviation.ToString();

                 }

             }