为多列单独汇总数据 table

Question

我正在尝试尽可能自动汇总多列数据，而不是为每一列单独编写代码。我想总结一下：

Patch    Size       Achmil  Aciarv   Aegpod Agrcap
  A       10            0       1      1      0
  B       2             1       0      0      0
  C       2             1       0      0      0
  D       2             1       0      0      0

进入这个

Species   Presence      MaxSize    MeanSize    Count
Achmil       0             10         10         1
Achmil       1             2           2         3
Aciarv       0             2           2         3
Aciarv       1             10          10        1

我知道我可以单独运行 group_by 并对每一列进行总结

achmil<-group_by(LimitArea, Achmil) %>%
  summarise(SumA=mean(Size))

但是有没有办法使用某种循环自动运行每个列的每个存在和不存在？任何帮助表示赞赏。

Answer 1

也许我们需要 gather 为长格式，然后执行 summarise

library(tidyverse)
gather(df1, Species, Presence, Achmil:Agrcap) %>% 
      group_by(Species, Presence)  %>% 
      summarise( MaxSize = max(Size), MeanSize = mean(Size), Count = n())
# A tibble: 7 x 5
# Groups: Species [?]
#  Species Presence MaxSize MeanSize Count
#  <chr>      <int>   <dbl>    <dbl> <int>
#1 Achmil         0   10.0     10.0      1
#2 Achmil         1    2.00     2.00     3
#3 Aciarv         0    2.00     2.00     3
#4 Aciarv         1   10.0     10.0      1
#5 Aegpod         0    2.00     2.00     3
#6 Aegpod         1   10.0     10.0      1
#7 Agrcap         0   10.0      4.00     4

在较新版本的dplyr/tidyr中，我们可以使用pivot_longer

df1 %>% 
   pivot_longer(cols = Achmil:Agrcap, names_to = "Species",
              values_to = "Presence") %>%
   group_by(Species, Presence) %>% 
   summarise(MaxSize = max(Size), MeanSize = mean(Size), Count = n())

Answer 2

这里是另一个使用聚合的解决方案（和 reshape2::melt()）

library(reshape2)

df = melt(df[,2:ncol(df)], "Size")
aggregate(. ~ `variable`+`value`, data = df, 
          FUN = function(x) c(max = max(x), mean = mean(x), count = length(x)))

    variable value Size.max Size.mean Size.count
1   Achmil     0       10        10          1
2   Aciarv     0        2         2          3
3   Aegpod     0        2         2          3
4   Agrcap     0       10         4          4
5   Achmil     1        2         2          3
6   Aciarv     1       10        10          1
7   Aegpod     1       10        10          1

为多列单独汇总数据 table

Summarize data table individually for multiple columns

r

dataframe

dplyr

summarize