我的数据是这样的:
data("Titanic")
df <- as.data.frame(Titanic)
我该如何取消聚合或反向汇总计数/频率并将数据集扩展回其原始的非计数观察状态?
例如,我希望在数据框中重复3rd, Male, Child, No
35次和1st, Female, Adult, Yes
140次,等等。
提前感谢。
dplyr
/tidyr
/purrr
动词来完成此操作。虽然它可能不像其他基本 R 解决方案那样紧凑,但对我来说更容易理解事物如何配合,并且在更大的 tidyverse
管道中运行。library(dplyr)
library(tidyr)
library(purrr)
sum(df$Freq)
#> [1] 2201
tibble
可以更轻松地查看和处理列表列。我使用purrr::map
沿着Freq
列移动,创建一个长度为Freq
值的虚拟标记向量。在这种情况下,该标记只是“1”,它也可以是TRUE
或其他任何东西。重点是它将创建一个长度为Freq
的向量。df %>%
as_tibble() %>%
mutate(obs = map(Freq, ~rep_len(1, .x)))
#> # A tibble: 32 x 6
#> Class Sex Age Survived Freq obs
#> <fct> <fct> <fct> <fct> <dbl> <list>
#> 1 1st Male Child No 0 <dbl [0]>
#> 2 2nd Male Child No 0 <dbl [0]>
#> 3 3rd Male Child No 35 <dbl [35]>
#> 4 Crew Male Child No 0 <dbl [0]>
#> 5 1st Female Child No 0 <dbl [0]>
#> 6 2nd Female Child No 0 <dbl [0]>
#> 7 3rd Female Child No 17 <dbl [17]>
#> 8 Crew Female Child No 0 <dbl [0]>
#> 9 1st Male Adult No 118 <dbl [118]>
#> 10 2nd Male Adult No 154 <dbl [154]>
#> # … with 22 more rows
然后tidyr::unnest
会为该虚拟向量中的每个元素创建一行。之后,我删除那最后2列,只保留重要的类别(class)、性别(sex)、年龄(age)和生存情况(survival)。
df %>%
as_tibble() %>%
mutate(obs = map(Freq, ~rep_len(1, .x))) %>%
unnest() %>%
select(-Freq, -obs)
#> # A tibble: 2,201 x 4
#> Class Sex Age Survived
#> <fct> <fct> <fct> <fct>
#> 1 3rd Male Child No
#> 2 3rd Male Child No
#> 3 3rd Male Child No
#> 4 3rd Male Child No
#> 5 3rd Male Child No
#> 6 3rd Male Child No
#> 7 3rd Male Child No
#> 8 3rd Male Child No
#> 9 3rd Male Child No
#> 10 3rd Male Child No
#> # … with 2,191 more rows
df2 <- df[rep(1:nrow(df), df[,5]),-5]
untable
函数来实现此操作。data("Titanic")
df <- as.data.frame(Titanic)
library(reshape)
newDf = untable(df[,1:4], num = df[,5])
library(tidyverse)
original <- tibble(x = c(1,1,1,2,2,2,4,4,4))
aggregated <- original %>% count(x)
deaggregated <- aggregated %>% uncount(weights = n)