如何根据开始和结束条件过滤数据？

我试图根据依赖于连续日期的两个条件来过滤数据。

• 我在寻找对于 5 个以上的连续日期，值低于 2,
• with a “缓冲期” of 值 2 到 5 最多连续 3 天.

它看起来像这样（很抱歉这里的 Excel 尝试很糟糕）:

第 1 天到第 10 天将包括在内，第 11 天将不包括在内。第 6 天到第 8 天将被视为“缓冲期”。我希望这是有道理的！！

现在，我可以获得缓冲期（在代表中）仅但我不知道如何添加开始和结束条件 对于小于 2 的值5 个连续日期被包括 （这 5 天可能会因中间的缓冲期而被打破，但我觉得这可能会让事情变得复杂).

任何帮助将不胜感激！

对于我的代表（below），最终 df 中包含的日期为蓝色（日期从 1/1/2000 到 1/9/2000，以及 1/22/2000 到 1/30/2000），而灰色日期则不会是。

Reprex:

    library("dplyr")
#Goal: include all values with values of 2 or less for 5 consecutive days and allow for a "cushion" period of values of 2 to 5 for up to 3 days
data <- data.frame(Date = c("2000-01-01", "2000-01-02", "2000-01-03", "2000-01-04", "2000-01-05", "2000-01-06", "2000-01-07", "2000-01-08", "2000-01-09", "2000-01-10", "2000-01-11", "2000-01-12", "2000-01-13", "2000-01-14", "2000-01-15", "2000-01-16", "2000-01-17", "2000-01-18", "2000-01-19", "2000-01-20", "2000-01-21", "2000-01-22", "2000-01-23", "2000-01-24", "2000-01-25", "2000-01-26", "2000-01-27", "2000-01-28", "2000-01-29", "2000-01-30"),
               Value = c(2,3,4,5,2,2,1,0,1,8,7,9,4,5,2,3,4,5,7,2,6,0,2,1,2,0,3,4,0,1))

head(data)                   
#Goal: values should include dates from 1/1/2000 to 1/9/2000, and 1/22/2000 to 1/30/2000

#I am able to subset the "cushion period" but I'm not sure how to add the starting and ending conditions for it
attempt1 <- data %>% 
  group_by(group_id = as.integer(gl(n(),3,n()))) %>% 
  filter(Value <= 5 & Value >=3) %>% 
  ungroup() %>% 
  select(-group_id)

head(attempt1)

如果我理解正确，则需要保留小于或等于 5 的连续值组，其中至少有 5 个小于或等于 2 的连续值。这是一种方法，并附有一些解释：

library(dplyr)

data %>% 
  mutate(under_three = Value <= 2) %>% 
  # under_three = TRUE if Value is below or equal to 2

  group_by(rl_two = data.table::rleid(Value <= 2)) %>%
  # Group by sequence of values that are under_three

  mutate(big = n() >= 5 & all(under_three)) %>%
  # big = T if there are more 5 or more consecutive values that are below or equal to 2  

  group_by(rl_five = data.table::rleid(Value <= 5)) %>% 
  # ungroup by rl_two, and group by rl_five, i.e. consecutive values that are below or equal to 5

  filter(any(big))
  # keep from the data frame groups of rl_five if they have at least one big = T; remove other groups.

Output:

data %>%
  ungroup() %>% 
  select(Date, Value)

   Date       Value
 1 2000-01-01     2
 2 2000-01-02     3
 3 2000-01-03     4
 4 2000-01-04     5
 5 2000-01-05     2
 6 2000-01-06     2
 7 2000-01-07     1
 8 2000-01-08     0
 9 2000-01-09     1
10 2000-01-22     0
11 2000-01-23     2
12 2000-01-24     1
13 2000-01-25     2
14 2000-01-26     0
15 2000-01-27     3
16 2000-01-28     4
17 2000-01-29     0
18 2000-01-30     1