BBIBOLL:=(MA(CV，3)+MA(CV，6)+MA(CV， 12)+MA(CV，24))/4；
UPR:=BBIBOLL+M*STD(BBIBOLL，N)；
DWN:=BBIBOLL-M*STD(BBIBOLL，N)；
XG: cross (DWN, c);
The parameter setting is the same as the original formula.
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