r - 根据R中的单独列标记列中值的第一次连续出现

问题描述

无法弄清楚这个......我在R中有一个像这样的数据集：

x <- c("A", "B", "C", "A", "A", "A", "C", "B", "A", "A", "B", "B", "A", "A", "C", "B","A")
z <- c(1, 1, 1, 1,2, 2, 2, 2, 2, 2, 2,3, 3, 3, 3, 3,3)
y <- c(43, 32, 12, 32, 22, 42, 45, 13, 15, 61, 71, 13, 32, 24, 11, 15,33)
df <- data.frame(x,z,y)

像这样：

现在我想标记 A 的第一次出现，如果它们在 z 的每个值中是连续的。
理想情况下，最终结果应如下所示：

我也很高兴收到有关如何改写这个问题的标题以使其更直接的建议。谢谢！

标签： rdataframemultiple-columns

x <- c("A", "B", "C", "A", "A", "A", "C", "B", "A", "A", "B", "B", "A", "A", "C", "B","A")
z <- c(1, 1, 1, 1,2, 2, 2, 2, 2, 2, 2,3, 3, 3, 3, 3,3)
y <- c(43, 32, 12, 32, 22, 42, 45, 13, 15, 61, 71, 13, 32, 24, 11, 15,33)
df <- data.frame(x,z,y)

library(dplyr)
library(data.table)

df %>%
  group_by(z) %>%                    # for each z
  mutate(id = rleid(x),              # create group based on consecutive values
         tag = cumsum(x == "A")) %>% # create group based on consecutive As
  group_by(z, id) %>%                # for each z and id
  mutate(tag = ifelse(x == "A" & min(tag) == 1, min(tag), 0)) %>%  # tag cases where we have the 1st A or As
  ungroup() %>%                      # forget the grouping
  select(-id)                        # remove id column

# # A tibble: 17 x 4
#   x         z     y   tag
#   <fct> <dbl> <dbl> <dbl>
# 1 A         1    43     1
# 2 B         1    32     0
# 3 C         1    12     0
# 4 A         1    32     0
# 5 A         2    22     1
# 6 A         2    42     1
# 7 C         2    45     0
# 8 B         2    13     0
# 9 A         2    15     0
#10 A         2    61     0
#11 B         2    71     0
#12 B         3    13     0
#13 A         3    32     1
#14 A         3    24     1
#15 C         3    11     0
#16 B         3    15     0
#17 A         3    33     0

r - 根据R中的单独列标记列中值的第一次连续出现

问题描述

解决方案

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