How to sort an R data frame rows in alphabetical order?

If we have string data stored in R data frame columns then we might want to sort the data frame rows in alphabetical order. This can be done with the help of apply and sort function inside transpose function.

For example, if we have a data frame called df that contains string data then sorting of df in alphabetical order can be done by using the below given command −

t(apply(df,1,sort))

Example 1

Following snippet creates a sample data frame −

x1<-sample(LETTERS[1:26],20) x2<-sample(LETTERS[1:26],20) x3<-sample(LETTERS[1:26],20) df1<-data.frame(x1,x2,x3) df1

Output

The following dataframe is created −

   x1 x2 x3 1  Z  L  Y 2  Q  W  J 3  P  S  Z 4  U  E  C 5  M  C  K 6  H  G  M 7  L  A  I 8  F  Q  T 9  R  T  G 10 X  N  P 11 T  I  L 12 N  J  E 13 E  X  R 14 Y  U  N 15 W  D  W 16 S  M  F 17 B  O  V 18 A  B  U 19 I  Z  D 20 O  F  A

To sort df1 rows in alphabetical order, add the following code to the above snippet −

x1<-sample(LETTERS[1:26],20) x2<-sample(LETTERS[1:26],20) x3<-sample(LETTERS[1:26],20) df1<-data.frame(x1,x2,x3) t(apply(df1,1,sort))

Output

If you execute all the above given codes as a single program, it generates the following output −

       [,1] [,2] [,3] [1,]  "L"  "Y"  "Z" [2,]  "J"  "Q"  "W" [3,]  "P"  "S"  "Z" [4,]  "C"  "E"  "U" [5,]  "C"  "K"  "M" [6,]  "G"  "H"  "M" [7,]  "A"  "I"  "L" [8,]  "F"  "Q"  "T" [9,]  "G"  "R"  "T" [10,] "N"  "P"  "X" [11,] "I"  "L"  "T" [12,] "E"  "J"  "N" [13,] "E"  "R"  "X" [14,] "N"  "U"  "Y" [15,] "D"  "W"  "W" [16,] "F"  "M"  "S" [17,] "B"  "O"  "V" [18,] "A"  "B"  "U" [19,] "D"  "I"  "Z" [20,] "A"  "F"  "O"

Example 2

Following snippet creates a sample data frame −

y1<-sample(c("India","Russia","China"),20,replace=TRUE) y2<-sample(c("UK","USA","Egpyt"),20,replace=TRUE) y3<-sample(c("Sudan","Nepal","Croatia"),20,replace=TRUE) df2<-data.frame(y1,y2,y3) df2

Output

The following dataframe is created −

     y1    y2    y3 1  India  UK    Nepal 2  India  Egpyt Sudan 3  China  USA   Nepal 4  China  USA   Sudan 5  Russia UK    Nepal 6  India  Egpyt Sudan 7  India  UK    Croatia 8  China  USA   Nepal 9  India  Egpyt Nepal 10 Russia UK    Croatia 11 Russia UK    Nepal 12 India  UK    Croatia 13 Russia USA   Nepal 14 Russia Egpyt Nepal 15 India  Egpyt Croatia 16 India  Egpyt Nepal 17 China  UK    Nepal 18 India  UK    Sudan 19 India  Egpyt Croatia 20 Russia USA    Nepal

To sort df2 rows in alphabetical order, add the following code to the above snippet −

y1<-sample(c("India","Russia","China"),20,replace=TRUE) y2<-sample(c("UK","USA","Egpyt"),20,replace=TRUE) y3<-sample(c("Sudan","Nepal","Croatia"),20,replace=TRUE) df2<-data.frame(y1,y2,y3) t(apply(df2,1,sort))

Output

If you execute all the above given codes as a single program, it generates the following output −

         [,1]     [,2]     [,3] [1,]  "India"  "Nepal"   "UK" [2,]  "Egpyt"  "India"   "Sudan" [3,]  "China"  "Nepal"   "USA" [4,]  "China"  "Sudan"   "USA" [5,]  "Nepal"  "Russia"  "UK" [6,]  "Egpyt"  "India"   "Sudan" [7,]  "Croatia" "India"  "UK" [8,]  "China"  "Nepal"   "USA" [9,]  "Egpyt"  "India"   "Nepal" [10,] "Croatia" "Russia" "UK" [11,] "Nepal"  "Russia"   "UK" [12,] "Croatia" "India"  "UK" [13,] "Nepal"  "Russia"  "USA" [14,] "Egpyt"  "Nepal"   "Russia" [15,] "Croatia" "Egpyt"  "India" [16,] "Egpyt"  "India"   "Nepal" [17,] "China"  "Nepal"   "UK" [18,] "India"  "Sudan"   "UK" [19,] "Croatia" "Egpyt"  "India" [20,] "Nepal"  "Russia"  "USA"