把图中出现买入红色箭头且K线为黄色时做预警公式

编写要求：

买线:=EMA(C,3); 趋势下降线:=EMA(SLOPE(C,21)*20+C,42); 趋势线:趋势下降线,COLORGREEN,LINETHICK2; IF(C>趋势线 AND 趋势线 >=REF(趋势线 ,1), 趋势线 ,DRAWNULL),LINETHICK2,COLORRED; BU:=CROSS(买线,趋势下降线); SEL:=CROSS(趋势下降线,买线); DRAWICON(BU,L-0.1,1); DRAWICON(SEL,H+0.1,2); STICKLINE(买线>=趋势下降线,LOW,HIGH,0.0,1),COLORRED; STICKLINE(买线>=趋势下降线,CLOSE,OPEN,3,1),COLORRED; STICKLINE(买线<趋势下降线,LOW,HIGH,0.0,1),COLORGREEN; STICKLINE(买线<趋势下降线,CLOSE,OPEN,3,1),COLORGREEN; STICKLINE(BU,OPEN,CLOSE,3,0),COLORYELLOW; STICKLINE(SEL,OPEN,CLOSE,3,0),COLORBLUE; VAR21:=LLV(LOW,10); VAR31:=HHV(HIGH,25); 阶段卖出:=3.2,COLORC6C600; 动力线:=EMA((CLOSE-VAR21)/(VAR31-VAR21)*4,4),COLORYELLOW,LINETHICK2; 清仓卖出:=3.5,COLORFF75FF; 底部:=0.2,COLOR70DB93; 关注:=0.5,COLORYELLOW; DRAWTEXT( FILTER(CROSS(动力线,关注),20),L*1,'底'); DRAWTEXT( FILTER(CROSS(动力线,底部),20),L*1,'多'); DRAWTEXT( FILTER(CROSS(阶段卖出,动力线),20),H*1,'顶'); DRAWTEXT( FILTER(CROSS(清仓卖出,动力线),20),H*1,'空'); DRAWTEXT_FIX(1,0.6,0,0,'操盘原则 黄多 兰空 红持股 绿持币 '),COLORYELLOW;

解答：

?买线:=EMA(C,3);

趋势下降线:=EMA(SLOPE(C,21)*20+C,42); ?