r - 识别向量中的给定模式并添加缺少的元素以获得给定模式的重复

Question

这个问题与这个Wide a dataframe 和 insert missing columns有关

假设我们有一个按以下顺序包含 5 个元素的给定模式："A", "B", "C", "D", "E"

这种模式重复说 10 次。但有时缺少一些元素（参见图片我的矢量（橙色）。

是否可以R识别重复的模式并填充缺少的元素（参见图片我想要的输出）。

我的载体：

my.vector <- c("A", "B", "C", "D", "E", "A", "B", "C", "D", "E", "B", "C", 
               "D", "E", "B", "C", "D", "E", "B", "C", "D", "E", "B", "C", "D", 
               "E", "B", "C", "D", "E", "B", "C", "D", "E", "A", "B", "C", "D", 
               "E", "B")

my.vector
 [1] "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "B" "C" "D" "E" "B" "C" "D" "E" "B" "C" "D" "E" "B" "C" "D" "E" "B" "C" "D" "E" "B" "C" "D" "E" "A" "B" "C" "D" "E" "B"

图形解释：

给定模式：

我的载体：

我想要的输出：要添加的红色标记元素

标签： rpattern-matchingsequence

Answer 1

使用, （或使用任何分组函数等）创建基于diffof matching 索引的分组列，并使用 'LETTERS[1:5] unlist list unname`创建一个LETTERS[1:5]splittapplyunion, theand

unname( unlist(lapply(split(my.vector, cumsum(c(TRUE, 
     diff(match(my.vector, LETTERS[1:5])) != 1))),
       function(x) union(LETTERS[1:5], x))))

-输出

[1] "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A"
[37] "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E"

---

或者另一种选择是complete

library(dplyr)
library(tidyr)
library(data.table)
tibble(col1 = my.vector) %>%
    group_by(rn = rowid(col1)) %>%
    complete(col1 = LETTERS[1:5]) %>%
    ungroup %>%
    pull(col1)

-输出

1] "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E" "A"
[37] "B" "C" "D" "E" "A" "B" "C" "D" "E" "A" "B" "C" "D" "E"