How to sort columns alphabetically

tidyselect

tidyverse

Published

November 17, 2022

In this tutorial, we will learn how to sort columns of a dataframe in alphabetical order. We will first use tidyverse to sort columns of a dataframe using two different ways. And then we will see how to use base R functions to sort the columns.

Let us load tidyverse.

library(tidyverse)

We will use starwars that is built-in with dplyr package. Let us look at the column names of starwars dataframe.

starwars %>% colnames()

 [1] "name"       "height"     "mass"       "hair_color" "skin_color"
 [6] "eye_color"  "birth_year" "sex"        "gender"     "homeworld" 
[11] "species"    "films"      "vehicles"   "starships"

Sorting columns with tidyverse

Using order() function on the column names we can order the column names in alphabatical order. This gives us a vector with ordered column names and we can use select() function from dplyr to select the ordered columns

starwars %>% 
  select(order(colnames(.))) 

# A tibble: 87 × 14
   birth_year eye_color films     gender hair_color height homeworld  mass name 
                                  
 1       19   blue       mascu… blond         172 Tatooine     77 Luke…
 2      112   yellow     mascu…           167 Tatooine     75 C-3PO
 3       33   red        mascu…            96 Naboo        32 R2-D2
 4       41.9 yellow     mascu… none          202 Tatooine    136 Dart…
 5       19   brown      femin… brown         150 Alderaan     49 Leia…
 6       52   blue       mascu… brown, gr…    178 Tatooine    120 Owen…
 7       47   blue       femin… brown         165 Tatooine     75 Beru…
 8       NA   red        mascu…            97 Tatooine     32 R5-D4
 9       24   brown      mascu… black         183 Tatooine     84 Bigg…
10       57   blue-gray  mascu… auburn, w…    182 Stewjon      77 Obi-…
# … with 77 more rows, and 5 more variables: sex , skin_color ,
#   species , starships , vehicles

We can see that after ordering the column names are alphabetical order.

starwars %>% 
  select(order(colnames(.))) %>%
  colnames()

 [1] "birth_year" "eye_color"  "films"      "gender"     "hair_color"
 [6] "height"     "homeworld"  "mass"       "name"       "sex"       
[11] "skin_color" "species"    "starships"  "vehicles"

Sorting columns using tidyselect’s peek_vars()

Another approach to sort columns using tidyverse is to use tidyselect’s peek_vars() function with sort() function as shown below.

starwars %>% 
  select(sort(tidyselect::peek_vars())) %>%
  colnames()

 [1] "birth_year" "eye_color"  "films"      "gender"     "hair_color"
 [6] "height"     "homeworld"  "mass"       "name"       "sex"       
[11] "skin_color" "species"    "starships"  "vehicles"

Sorting columns using base R

We can also sort the columns using base R funntions alone. Here we use order() function on the column names and use [] to select the ordered columns.

starwars[, order(colnames(starwars))]

# A tibble: 87 × 14
   birth_year eye_color films     gender hair_color height homeworld  mass name 
                                  
 1       19   blue       mascu… blond         172 Tatooine     77 Luke…
 2      112   yellow     mascu…           167 Tatooine     75 C-3PO
 3       33   red        mascu…            96 Naboo        32 R2-D2
 4       41.9 yellow     mascu… none          202 Tatooine    136 Dart…
 5       19   brown      femin… brown         150 Alderaan     49 Leia…
 6       52   blue       mascu… brown, gr…    178 Tatooine    120 Owen…
 7       47   blue       femin… brown         165 Tatooine     75 Beru…
 8       NA   red        mascu…            97 Tatooine     32 R5-D4
 9       24   brown      mascu… black         183 Tatooine     84 Bigg…
10       57   blue-gray  mascu… auburn, w…    182 Stewjon      77 Obi-…
# … with 77 more rows, and 5 more variables: sex , skin_color ,
#   species , starships , vehicles

starwars[, order(colnames(starwars))] %>% colnames()

 [1] "birth_year" "eye_color"  "films"      "gender"     "hair_color"
 [6] "height"     "homeworld"  "mass"       "name"       "sex"       
[11] "skin_color" "species"    "starships"  "vehicles"

https://stackoverflow.com/questions/29873293/dply-order-columns-alphabetically-in-r

--- title: "How to sort columns alphabetically" date: 2022-11-17 categories: ['tidyselect', 'tidyverse'] format: html: code-fold: false code-tools: true --- In this tutorial, we will learn how to sort columns of a dataframe in alphabetical order. We will first use tidyverse to sort columns of a dataframe using two different ways. And then we will see how to use base R functions to sort the columns. Let us load tidyverse. ```r library(tidyverse) ``` We will use starwars that is built-in with dplyr package. Let us look at the column names of starwars dataframe. ```r starwars %>% colnames() [1] "name" "height" "mass" "hair_color" "skin_color" [6] "eye_color" "birth_year" "sex" "gender" "homeworld" [11] "species" "films" "vehicles" "starships" ``` ### Sorting columns with tidyverse Using order() function on the column names we can order the column names in alphabatical order. This gives us a vector with ordered column names and we can use select() function from dplyr to select the ordered columns ```r starwars %>% select(order(colnames(.))) # A tibble: 87 × 14 birth_year eye_color films gender hair_color height homeworld mass name 1 19 blue mascu… blond 172 Tatooine 77 Luke… 2 112 yellow mascu… 167 Tatooine 75 C-3PO 3 33 red mascu… 96 Naboo 32 R2-D2 4 41.9 yellow mascu… none 202 Tatooine 136 Dart… 5 19 brown femin… brown 150 Alderaan 49 Leia… 6 52 blue mascu… brown, gr… 178 Tatooine 120 Owen… 7 47 blue femin… brown 165 Tatooine 75 Beru… 8 NA red mascu… 97 Tatooine 32 R5-D4 9 24 brown mascu… black 183 Tatooine 84 Bigg… 10 57 blue-gray mascu… auburn, w… 182 Stewjon 77 Obi-… # … with 77 more rows, and 5 more variables: sex , skin_color , # species , starships , vehicles ``` We can see that after ordering the column names are alphabetical order. ```r starwars %>% select(order(colnames(.))) %>% colnames() [1] "birth_year" "eye_color" "films" "gender" "hair_color" [6] "height" "homeworld" "mass" "name" "sex" [11] "skin_color" "species" "starships" "vehicles" ``` ### Sorting columns using tidyselect's peek_vars() Another approach to sort columns using tidyverse is to use tidyselect's peek_vars() function with sort() function as shown below. ```r starwars %>% select(sort(tidyselect::peek_vars())) %>% colnames() [1] "birth_year" "eye_color" "films" "gender" "hair_color" [6] "height" "homeworld" "mass" "name" "sex" [11] "skin_color" "species" "starships" "vehicles" ``` ### Sorting columns using base R We can also sort the columns using base R funntions alone. Here we use order() function on the column names and use [] to select the ordered columns. ```r starwars[, order(colnames(starwars))] # A tibble: 87 × 14 birth_year eye_color films gender hair_color height homeworld mass name 1 19 blue mascu… blond 172 Tatooine 77 Luke… 2 112 yellow mascu… 167 Tatooine 75 C-3PO 3 33 red mascu… 96 Naboo 32 R2-D2 4 41.9 yellow mascu… none 202 Tatooine 136 Dart… 5 19 brown femin… brown 150 Alderaan 49 Leia… 6 52 blue mascu… brown, gr… 178 Tatooine 120 Owen… 7 47 blue femin… brown 165 Tatooine 75 Beru… 8 NA red mascu… 97 Tatooine 32 R5-D4 9 24 brown mascu… black 183 Tatooine 84 Bigg… 10 57 blue-gray mascu… auburn, w… 182 Stewjon 77 Obi-… # … with 77 more rows, and 5 more variables: sex , skin_color , # species , starships , vehicles ``` ```r starwars[, order(colnames(starwars))] %>% colnames() [1] "birth_year" "eye_color" "films" "gender" "hair_color" [6] "height" "homeworld" "mass" "name" "sex" [11] "skin_color" "species" "starships" "vehicles" ``` https://stackoverflow.com/questions/29873293/dply-order-columns-alphabetically-in-r