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))
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
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))
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"
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
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))
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"