将多列的值传递给 dplyr 汇总函数

Question

请考虑以下最小示例：我将两个实验 A 和 B 的观察结果合并为 dplyr tibble。 llim 和 ulim 定义每组中可观察值的下限和上限。

library(dplyr)

name <- factor  (c  (rep('A', 400), 
                    rep('B', 260)
                    )
                )

obs <- c    (sample(-23:28, 400, replace = TRUE),
            sample(-15:39, 260, replace = TRUE)
            )

llim <- c   (rep(-23, 400), 
            rep(-15, 260)
            )

ulim <- c   (rep(28, 400), 
            rep(39, 260)
            )

tib1 <- tibble  (name, obs, llim, ulim)

tib1
# A tibble: 660 x 4
   name    obs  llim  ulim
   <fct> <int> <dbl> <dbl>
 1 A        22   -23    28
 2 A        -5   -23    28
 3 A         2   -23    28
 4 A         9   -23    28
 5 A        -1   -23    28
 6 A       -21   -23    28
 7 A        13   -23    28
 8 A         0   -23    28
 9 A         8   -23    28
10 A       -11   -23    28
# … with 650 more rows

接下来，我计算每组可观察值的直方图。只要我使用 hist().

的默认参数，这就可以正常工作

tib1 %>%    group_by(name) %>%

            summarise   (counts = hist(obs, plot = FALSE)$counts)

`summarise()` has grouped output by 'name'. You can override using the `.groups` argument.
# A tibble: 22 x 2
# Groups:   name [2]
   name  counts
   <fct>  <int>
 1 A         26
 2 A         44
 3 A         39
 4 A         32
 5 A         42
 6 A         34
 7 A         44
 8 A         41
 9 A         39
10 A         37
# … with 12 more rows

现在，我想使用存储在 tibble 中的其他组特定参数来调整这些直方图，例如llim 和 ulim。然而，这似乎不起作用：

tib1 %>%    group_by(name) %>%

            summarise   (counts = hist  (obs, 
                                        breaks = seq    (llim,
                                                        ulim,
                                                        by = 1
                                                        ),
                                        plot = FALSE
                                        )$counts
                        )
Error: Problem with `summarise()` input `counts`.
✖ 'from' must be of length 1
ℹ Input `counts` is `hist(obs, breaks = seq(llim, ulim, by = 1), plot = FALSE)$counts`.
ℹ The error occurred in group 1: name = "A".
Run `rlang::last_error()` to see where the error occurred.

有没有办法将列 llim 和 ulim 的值传递给 hist() 函数？还是有其他问题？错误信息有点含糊...

非常感谢您的帮助！

Answer 1

这给出了 obs 按组 name

的直方图

library(ggplot2)
ggplot(tib1, aes(x = obs)) +
  geom_histogram(aes(color = name, fill = name),
                 position = "identity", bins = 30, alpha = 0.4) +
  scale_color_manual(values = c("blue", "red")) +
  scale_fill_manual(values = c("blue", "red"))

Answer 2

将 llim 和 ulim 的长度减少到 1（例如使用 max() 或 min()）就可以了：

tib1 %>%    group_by(name, llim, ulim) %>%

            summarise   (counts = hist  (obs, 
                                        breaks = seq    (max(llim),
                                                        max(ulim),
                                                        by = 1
                                                        ),
                                        plot = FALSE
                                        )$counts
                        )
# A tibble: 105 x 4
# Groups:   name, llim, ulim [2]
   name   llim  ulim counts
   <fct> <dbl> <dbl>  <int>
 1 A       -23    28      9
 2 A       -23    28      9
 3 A       -23    28      8
 4 A       -23    28      7
 5 A       -23    28      5
 6 A       -23    28      8
 7 A       -23    28     14
 8 A       -23    28     10
 9 A       -23    28      9
10 A       -23    28      9
# … with 95 more rows

所以错误信息最终是有道理的...

将多列的值传递给 dplyr 汇总函数

passing values from multiple columns into dplyr summarise function

r

dplyr

histogram

summarize