sar指标选股公式以及源码

刚发现有人要sar的源码
一并发上来A:IF(CLOSE>SAR(4,2,20),SAR(4,2,20),DRAWNULL),CIRCLEDOT,COLORRED;
B:IF(CLOSE<SAR(4,2,20),SAR(4,2,20),DRAWNULL),CIRCLEDOT,COLORCYAN;
STICKLINE(CLOSE>=OPEN,CLOSE,CLOSE,2,1),COLORRED;
STICKLINE(CLOSE>=OPEN,LOW,HIGH,0,1),COLORRED;
STICKLINE(CLOSE<=OPEN,LOW,HIGH ,0,1),COLORCYAN;
STICKLINE(CLOSE<=OPEN,CLOSE,CLOSE,2 ,1 ),COLORCYAN;

这个是选股源码
REF(CLOSE>SAR(4,2,20),1) AND CLOSE<SAR(4,2,20);