R - 如何在保持分组的同时重新排列数据框中的行？

Question

我有以下数据框。这些行目前按物种组排序，即高粱组后跟禾本科组。

# create a dataset
specie <- c(rep("sorgho" , 3) , rep("poacee" , 3) , rep("banana" , 3) , rep("triticum" , 3) )
condition <- rep(c("normal" , "stress" , "Nitrogen") , 4)
value <- abs(rnorm(12 , 0 , 15))
data <- data.frame(specie,condition,value)
print(data)

     specie condition     value
1    sorgho    normal 12.623696
2    sorgho    stress 11.394047
3    sorgho  Nitrogen  0.498003
4    poacee    normal 14.589322
5    poacee    stress 10.744153
6    poacee  Nitrogen  7.299742
7    banana    normal  9.845850
8    banana    stress  9.416088
9    banana  Nitrogen  4.178521
10 triticum    normal 13.230663
11 triticum    stress 30.658355
12 triticum  Nitrogen  9.402721

我怎样才能重新排列这些分组，使它们按氮值递减的顺序排列？我希望将数据框重新组织为类似于以下内容:

     specie condition     value
10 triticum    normal 13.230663
11 triticum    stress 30.658355
12 triticum  Nitrogen  9.402721
4    poacee    normal 14.589322
5    poacee    stress 10.744153
6    poacee  Nitrogen  7.299742
7    banana    normal  9.845850
8    banana    stress  9.416088
9    banana  Nitrogen  4.178521
1    sorgho    normal 12.623696
2    sorgho    stress 11.394047
3    sorgho  Nitrogen  0.498003

Answer 1

我们可以filter “氮”行，arrange 'value' 按降序排列，提取 'specie' 并将其用作 levels '安排'specie'栏

library(dplyr)
lvls <- data %>% 
      filter(condition == 'Nitrogen') %>% 
      arrange(desc(value)) %>% 
      pull(specie) 
data %>% 
        arrange(factor(specie, levels = lvls))%>%
        as_tibble

-输出

# A tibble: 12 x 3
#   specie   condition  value
#   <chr>    <chr>      <dbl>
# 1 triticum normal    13.2  
# 2 triticum stress    30.7  
# 3 triticum Nitrogen   9.40 
# 4 poacee   normal    14.6  
# 5 poacee   stress    10.7  
# 6 poacee   Nitrogen   7.30 
# 7 banana   normal     9.85 
# 8 banana   stress     9.42 
# 9 banana   Nitrogen   4.18 
#10 sorgho   normal    12.6  
#11 sorgho   stress    11.4  
#12 sorgho   Nitrogen   0.498

或者在单个管道中执行此操作

data %>%
    arrange(factor(specie, levels = 
          unique(specie)[order(-value[condition == 'Nitrogen'])]))

或使用 base R

data[order(with(data, factor(specie, levels = 
     unique(specie)[order(-value[condition == "Nitrogen"])]))),]

数据

data <- structure(list(specie = c("sorgho", "sorgho", "sorgho", "poacee", 
"poacee", "poacee", "banana", "banana", "banana", "triticum", 
"triticum", "triticum"), condition = c("normal", "stress", "Nitrogen", 
"normal", "stress", "Nitrogen", "normal", "stress", "Nitrogen", 
"normal", "stress", "Nitrogen"), value = c(12.623696, 11.394047, 
0.498003, 14.589322, 10.744153, 7.299742, 9.84585, 9.416088, 
4.178521, 13.230663, 30.658355, 9.402721)), class = "data.frame",
row.names = c("1", 
"2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12"))