public static string Memebership2Grade(DenseVector memebershipVector)
 {
     int maxIndex=memebershipVector.MaximumIndex();
     if(maxIndex>EvaluatedFiveGrades.Count-1||maxIndex<0)
     {
         throw (new Exception("隶属度向量数量大于评估指标分级数"));
     }
     return EvaluatedFiveGrades[maxIndex];
 }