begt:=20181001T;
Endt:=20181030T;
Setsysparam(Pn_Stock(),"SZ000002");
dateArr:=markettradedayQK(begt,Endt);
data:=select thisrow as "日期",
       Spec(Specdate(close(),thisrow),"SZ000002") as "价格",
       SPec(Specdate(Close(),thisrow),"SH000001") as "大盘"
     from dateArr
     End;
return cov(data[:,"价格"],data[:,"大盘"]);