这是足够的数据来复制问题:structure(list(sensorheight=c(1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L,1L),yrmonth=structure(c(1459468800,1459468800,1459468800,1459468800,1459468800,1459468800,1459468800,1459468800,1459468800,1459468800,1462060800,1462060800,1462060800,1462060800,1462060800,1462060800,