oV := BackupSystemParameters2();
   //假设组合为申万采掘，先计算其下个股的区间beta
  stockArr := getbk('申万采掘');
  IndexId := 'SH000001';
  BegT := inttodate(20110101);
  EndT := inttodate(20110630);
  t := array();
  n := 0;
  for i:=0 to length(stockArr)-1 do
  begin
   stockid := stockArr[i];
   setsysparam(pn_stock(),stockid);
   if not IsStockGoMarket(begt) then continue;
   tmp := StockBetaAlpha2(IndexId,BegT,EndT);
   t[n]['代码'] := stockid;
   t[n]['名称'] := stockname(stockid);
   t[n]['beta'] := tmp['Beta'];
   n++;
  end
   //按总股本加权，计算组合beta
  t2 := pf_percent(t[:,'代码'],EndT,0);
  t := select [1].['beta'],[2].['比例(%)'] from t
     left join t2 with([1].['代码'] on [2].['代码'])
     end;
   return StocksBeta(t[:,'beta'],t[:,'比例(%)']);  //结果：1.0095