类似J2000的ECI坐标系转换到类似wgs84的ECEF坐标系,方便大家应用(Convert ECI (CIS, Epoch J2000.0) Coordinates to WGS 84 (CTS, ECEF) Coordinates. This function has been vectorized for speed. Example Function Call: >> [r_ECEF v_ECEF a_ECEF] = ECItoECEF(JD,r_ECI,v_EC