matlab函数调用问题

主函数如下：
function main
load Data
Share=GetData()
structData=AlfaData(NumOfSample,PosiDay,DayData,ShareData,ShareRate,IndexData,IndexRate)
structShare=SelectShare(structData,PosiDay,DayData,ShareData,ShareRate,IndexData,IndexRate,AlfaSt,BetaSt,CorrSt,StdevSt,TrackSt,NumSt)
其中structData为结构数组，运行时产生如下错误：
??? Undefined function or method 'SelectShare' for input arguments of type 'struct'.
Error in ==> main at 12
structShare=SelectShare(structData,PosiDay,DayData,ShareData,ShareRate,IndexData,IndexRate,AlfaSt,BetaSt,CorrSt,StdevSt,TrackSt,NumSt)
请问是怎么回事情哪？

进来看看 了解下