我的数据如下:
df <- structure(list(site = c("A", "A", "A", "A", "B", "B", "B", "B",
"A", "A", "A", "A", "B", "B", "B", "B"), year = c(2019L, 2019L,
2019L, 2019L, 2019L, 2019L, 2019L, 2019L, 2020L, 2020L, 2020L,
2020L, 2020L, 2020L, 2020L, 2020L), date = c("2019-08-12", "2019-08-14",
"2019-10-16", "2019-10-27", "2019-08-10", "2019-08-13", "2019-10-01",
"2019-10-16", "2020-08-08", "2020-08-11", "2020-10-14", "2020-10-16",
"2020-08-07", "2020-08-19", "2020-10-15", "2020-10-20")),
class = "data.frame", row.names = c(NA,
-16L))
对于每个站点和每年,我希望使用以下条件对日期范围进行子集:
从8月15日之前的最晚日期开始,到10月15日之后的最早日期结束.
提前感谢您!