排序NSMutableArray裏與float數據類型

Question

一鍵我有一個NSMutableArray的數據：

Name ... Male ... Age ... Point 
("David"..."Male"...18...7.25) 
("Mary"..."Female"...16...20.50) 
("Kend"..."Male"...17...4.50) 
("Frank"..."Male"...25...27.50) 
("Cain"..."Female"...28...2.25) 
("Sims"..."Female"...17...10.50) 

...

我想關鍵點這個的NSMutableArray進行排序。我想：

NSSortDescriptor *aSortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"Point" ascending:NO]; 
[self.arrayPupils sortUsingDescriptors:[NSArray arrayWithObject:aSortDescriptor]]; 

輸出：

David/Male/18/7.25 
Kend/Male/17/4.50 
Frank/Male/25/27.50 
Mary/Female/16/20.50 
Cain/Female/28/2.25 
Sims/Female/17/10.50 

但預期的結果是：

Frank/Male/25/27.50 
Mary/Female/16/20.50 
Sims/Female/17/10.50 
David/Male/18/7.25 
Kend/Male/17/4.50 
Cain/Female/28/2.25 

幫我請...非常感謝。

Answer 1

您的排序按年齡排序。你需要改爲按「點」來獲得輸出。