在股票中，怎么把这个指标改成选股指标？

买线:EMA(C,2),colorred;
卖线:EMA(SLOPE(C,21)*20+C,42),coloryellow;
SEL:=CROSS(卖线,买线);
DRAWTEXT(sel,(HIGH * 1.028),'↓'),colorwhite,linethick5;
DRAWTEXT(sel,(HIGH * 1.058),'S'),colorwhite,linethick5;
STICKLINE(买线>=卖线,LOW,HIGH,0.1,1),colorred;
STICKLINE(买线>=卖线,CLOSE,OPEN,8,1),colorred;
STICKLINE(买线>=卖线,CLOSE,OPEN,10,1),colorred;
STICKLINE(买线<卖线,CLOSE,OPEN,10,0),colorblue;
STICKLINE(买线<卖线,CLOSE,OPEN,8,0),colorblue;
STICKLINE(买线<卖线,LOW,HIGH,0.1,1),colorblue;
STICKLINE(CROSS(买线,卖线) OR CROSS(卖线,买线),OPEN,CLOSE,6,0),coloryellow;

买线:EMA(C,2),colorred;
卖线:EMA(SLOPE(C,21)*20+C,42),coloryellow;
BU:=CROSS(买线,卖线);
SEL:=CROSS(卖线,买线);
DRAWTEXT(bu,(LOW * 0.988),'↑'),colorred,linethick5;
DRAWTEXT(bu,(LOW * 0.958),'B'),colorred,linethick5;
DRAWTEXT(sel,(HIGH * 1.028),'↓'),colorwhite,linethick5;
DRAWTEXT(sel,(HIGH * 1.058),'S'),colorwhite,linethick5;
STICKLINE(买线>=卖线,LOW,HIGH,0.1,1),colorred;
STICKLINE(买线>=卖线,CLOSE,OPEN,8,1),colorred;
STICKLINE(买线>=卖线,CLOSE,OPEN,10,1),colorred;
STICKLINE(买线<卖线,CLOSE,OPEN,10,0),colorblue;
STICKLINE(买线<卖线,CLOSE,OPEN,8,0),colorblue;
STICKLINE(买线<卖线,LOW,HIGH,0.1,1),colorblue;
STICKLINE(CROSS(买线,卖线) OR CROSS(卖线,买线),OPEN,CLOSE,6,0),coloryellow;