r-根据缺少的小时数删除天数

Question

我有一些按小时测量的空气污染数据。

站点id

日期时间	PM2.5
2020-01-01 00:00:00	10	1
2020-01-01 01:00:00	NA	1
2020-01-01 02:00:00	15	1
2020-01-01 03:00:00	NA	1
2020-01-01 04:00:00	7	1
2020-01-01 05:00:00	20	1
2020-01-01 06:00:00	30	1
2020-01-01 00:00:00	NA	2
2020-01-01 01:00:00	17	2
2020-01-01 02:00:00	21	2
2020-01-01 03:00:00	55	2

；最有效的"方式几乎肯定会使用data.table。类似这样的东西：

library(data.table)
setDT(your_data)
your_data[, date := as.IDate(Datetime)][,
if(
!(sum(is.na(PM2.5)) >= 18 & 
with(rle(is.na(PM2.5)), max(lengths[values])) >= 8
)) .SD,
by = .(date, station.id)
]
#          date            Datetime PM2.5
# 1: 2020-01-01 2020-01-01 00:00:00    10
# 2: 2020-01-01 2020-01-01 01:00:00    NA
# 3: 2020-01-01 2020-01-01 02:00:00    15
# 4: 2020-01-01 2020-01-01 03:00:00    NA
# 5: 2020-01-01 2020-01-01 04:00:00     7
# 6: 2020-01-01 2020-01-01 05:00:00    20
# 7: 2020-01-01 2020-01-01 06:00:00    30

使用此示例数据：

your_data = fread(text = 'Datetime  PM2.5
2020-01-01 00:00:00 10
2020-01-01 01:00:00 NA
2020-01-01 02:00:00 15
2020-01-01 03:00:00 NA
2020-01-01 04:00:00 7
2020-01-01 05:00:00 20
2020-01-01 06:00:00 30')