我需要获得R中汇总列的相对频率。我使用dplyr的summary来找到每个分组行的总数,如下所示:
data %>%
group_by(x) %>%
summarise(total = sum(dollars))
x total
<chr> <dbl>
1 expense 1 3600
2 expense 2 2150
3 expense 3 2000
但现在我需要为每一行的相对频率创建一个新的列,以获得以下结果:
x total p
<chr> <dbl> <dbl>
1 expense 1 3600 46.45%
2 expense 2 2150 27.74%
3 expense 3 2000 25.81%
我试过这个:
data %>%
group_by(x) %>%
summarise(total = sum(dollars), p = scales::percent(total/sum(total))
这个:
data %>%
group_by(x) %>%
summarise(total = sum(dollars), p = total/sum(total)*100)
但结果总是这样:
x total p
<chr> <dbl> <dbl>
1 expense 1 3600 100%
2 expense 2 2150 100%
3 expense 3 2000 100%
问题似乎是汇总的总列可能会影响结果。有什么想法可以帮我吗?感谢
由于分组,您可以获得100%。然而,在您总结之后,dplyr将放弃一个级别的分组。这意味着,如果你在之后进行mutate()
,你会得到你需要的结果:
library(dplyr)
data <- tibble(
x = c("expense 1", "expense 2", "expense 3"),
dollars = c(3600L, 2150L, 2000L)
)
data %>%
group_by(x) %>%
summarise(total = sum(dollars)) %>%
mutate(p = total/sum(total)*100)
# A tibble: 3 x 3
x total p
<chr> <int> <dbl>
1 expense 1 3600 46.5
2 expense 2 2150 27.7
3 expense 3 2000 25.8
您可以获得100%,因为它计算了特定组的总数。你需要取消分组。假设您想除以总条目,只需除以nrow(df)
。
data %>%
group_by(x) %>%
summarise(total = sum(dollars), p = total/nrow(data)*100)
在第一个sum
之后,取消分组并使用mutate
创建p
。
iris %>%
group_by(Species) %>%
summarise(total = sum(Sepal.Length)) %>%
ungroup() %>%
mutate(p = total/sum(total)*100)
## A tibble: 3 x 3
# Species total p
# <fct> <dbl> <dbl>
#1 setosa 250. 28.6
#2 versicolor 297. 33.9
#3 virginica 329. 37.6