R:重新排列数据框中行的顺序

Question

我想重新排列数据的顺序。我有一个如下所示的数据集:

Animal<-c("bird","Bird ","Dog","Cat F","Lion","Lion","Lion","dog","Horse","cat", "Lion")

A_date<-c("02-08-2020","20-06-2018","01-01-2015","10-07-2021","20-06-2018","15-08-2019","05-08-2013","20-06-2010","15-11-2016","22-03-2022","15-05-2019")

ID<-c("T1", "T1","T1","T2","T2","T3","T3","T4","T4","T15","T15")

Mydata<-data.frame(Animal, A_date,ID)

 Animal   A_date       ID
bird     02-08-2020    T1
Bird     20-06-2018    T1
Dog      01-01-2015    T1
Cat F    10-07-2021    T2
Lion     20-06-2018    T2
Lion     15-08-2019    T3
lion     05-08-2013    T3
dog      20-06-2010    T4
Horse    15-11-2016    T4
cat      22-03-2022    T15
Lion     15-05-2019    T15

我使用下面的代码删除重复的行，以便仅删除具有最新日期的行。 ID 将保留。

library(lubridate)
library(dplyr)

Mydata %>%
  mutate(Animal = trimws(toupper(Animal)), A_date = lubridate::dmy(A_date)) %>%
  group_by(ID, Animal) %>%
  arrange(ID, Animal, -desc(A_date)) %>%
  slice(1)

输出如下所示:

  A tibble: 9 x 3
# Groups:   ID, Animal [9]
  Animal A_date     ID   
  <chr>  <date>     <chr>
1 BIRD   2018-06-20 T1   
2 DOG    2015-01-01 T1   
3 CAT    2022-03-22 T15  
4 LION   2019-05-15 T15  
5 CAT F  2021-07-10 T2   
6 LION   2018-06-20 T2   
7 LION   2013-08-05 T3   
8 DOG    2010-06-20 T4   
9 HORSE  2016-11-15 T4 

我想更改顺序，以便顺序应该为 pr。从最高ID开始的ID，最新日期。 我希望结果如下所示:

 Animal    A_date     ID   
      <chr>  <date>     <chr>
    CAT    2022-03-22 T15   
    LION   2019-05-15 T15
    HORSE  2016-11-15 T4    
    DOG    2010-06-20 T4   
    LION   2019-08-15 T3   
    CAT F  2021-07-10 T2   
    LION   2018-06-20 T2
    BIRD   2020-08-02 T1   
    DOG    2015-01-01 T1   
    

关于如何获得该结果有什么建议吗？

Answer 1

从 Mydata 作为您的最后一个输出:

Mydata <- Mydata %>% 
  ungroup %>% 
  arrange(desc(as.numeric(gsub("T","",ID))),
          desc(A_date))

输出

# A tibble: 9 x 3
  Animal A_date     ID   
  <chr>  <date>     <chr>
1 CAT    2022-03-22 T15  
2 LION   2019-05-15 T15  
3 HORSE  2016-11-15 T4   
4 DOG    2010-06-20 T4   
5 LION   2013-08-05 T3   
6 CAT F  2021-07-10 T2   
7 LION   2018-06-20 T2   
8 BIRD   2018-06-20 T1   
9 DOG    2015-01-01 T1  

我首先删除了分组，以便可以排列所有行，然后删除 ID 中的 T，将其转换为数字以按降序排列，然后像您之前所做的那样在日期上再次排列。

ID 为 T3 的 LION 和 T1 的 BIRD 日期在您的预期输出中可能不正确。如果不是这样，请告诉我，因为这意味着我不明白你的问题。