xcode NSNumber 轉float 最後一位小數錯誤

 記錄個還沒分析的現象：

NSNumber *num = @0.47;

int val= (int)([num floatValue ]*100.0);

此時val 爲46

 

 

NSNumber *num = @0.47;

int val= (int)([num floatValue ]*100);

或

NSNumber *num = @0.47;

int val= (int)([num floatValue ]*100.0f);

val纔是47