连续出现次数最多的值 - R

Question

我有一个如下所示的数据框：

week_0 <- c(5,0,1,0,0,1)
week_1 <- c(5,0,4,0,2,1)
week_2 <- c(5,0,4,0,8,1)
week_3 <- c(5,0,4,0,8,3)
week_4 <- c(1,0,4,0,8,3)
week_5 <- c(1,0,4,0,8,3)
week_6 <- c(1,0,4,0,1,3)
week_7 <- c(1,0,4,0,1,3)
week_8 <- c(1,0,6,0,3,4)
week_9 <- c(2,4,6,7,3,4)
week_10 <- c(2,4,6,7,3,4)
Participant <- c("Lion","Cat","Dog","Snake","Tiger","Mouse")
test_data <- data.frame(Participant,week_0,week_4,week_8,week_9,week_10)

>test_data

    Participant week_0 week_1 week_2 week_3 week_4 week_5 week_6 week_7 week_8 week_9 week_10
1        Lion      5      5      5      5      1      1      1      1      1      2       2
2         Cat      0      0      0      0      0      0      0      0      0      4       4
3         Dog      1      4      4      4      4      4      4      4      6      6       6
4       Snake      0      0      0      0      0      0      0      0      0      7       7
5       Tiger      0      2      8      8      8      8      1      1      3      3       3
6       Mouse      1      1      1      3      3      3      3      3      4      4       4

我想找出一行中比其他值出现更多的值。 例如，第一行的值为 1。我要返回的输出是第一行的 week_4。 对于第二行，出现次数多于其他的值是 0。我要返回的输出是 week_0 等... 所以最终的结果应该是： 第 4 周、第 0 周、第 1 周、第 0 周、第 2 周、第 3 周 我必须使用：

apply(test_data,1,function(x) names(which.max(table(x))))

但我没有得到我正在搜索的结果。

关于如何做到这一点有什么建议吗？

Answer 1

您的代码是良好的开端。您可以使用结果

match()

它在行中的第一个位置，然后使用这个位置索引到列名中：

apply(test_data[, -1], 1, function(x) {
  val <- names(which.max(table(x)))
  names(test_data)[-1][[match(val, x)]]
})
# "week_4" "week_0" "week_1" "week_0" "week_2" "week_3"

注意我用

test_data[, -1]

排除

Participant

列；否则，如果没有多次出现的值，代码将返回参与者姓名，这可能不是您想要的。

Answer 2

dplyr

解决方案

add_count

+

slice_max

:

library(dplyr)

test_data %>%
  tidyr::pivot_longer(starts_with('week')) %>%
  add_count(Participant, value) %>%
  slice_max(n, by = Participant, with_ties = FALSE)

# # A tibble: 6 × 4
#   Participant name   value     n
#   <chr>       <chr>  <dbl> <int>
# 1 Lion        week_4     1     2
# 2 Cat         week_0     0     3
# 3 Dog         week_8     6     3
# 4 Snake       week_0     0     3
# 5 Tiger       week_8     3     3
# 6 Mouse       week_8     4     3