# How to extract the names of vector values from a named vector in R?

How to extract the names of vector values from a named vector in R?

The names of vector values are created by using name function and the names can be extracted by using the same function. For example, if we have a vector called x that contains five values(1 to 5) and their names are defined as first, second, third, fourth and fifth then the names of values in x can be extracted by using names(x)[x==1].

## Example1

Live Demo

> x1<-1:4
> names(x1)<-c("one","two","three","four")
> x1

## Output

one two three four
1 2 3 4

## Example

> names(x1)[x1==1]

## Output

[1] "one"

## Example

> names(x1)[x1==2]

## Output

[1] "two"


## Example

> names(x1)[x1==3]

## Output

[1] "three"

## Example

> names(x1)[x1==4]

## Output

[1] "four"


## Example2

Live Demo

> x2<-sample(0:5,120,replace=TRUE)
> x2

## Output

 [1] 3 5 1 4 5 2 3 2 4 5 1 4 2 4 4 3 1 0 5 0 2 1 5 1 3 1 0 2 3 0 3 2 4 2 3 2 0
[38] 3 5 3 4 3 2 3 3 4 4 2 3 2 3 5 5 5 2 1 2 5 2 3 2 2 4 4 2 4 1 4 0 5 5 5 4 0
[75] 1 3 0 3 3 5 1 2 4 5 3 0 3 5 0 3 5 4 3 5 5 2 5 2 1 3 0 0 3 1 2 1 2 3 1 3 4
[112] 0 4 1 4 4 4 4 5 2

## Example

> names(x2)<-sample(c("India","Russia","Turkey","France","Germany"),120,replace=TRUE)
> x2

## Output

France Russia Russia Russia France Germany Germany France Turkey Germany
3 5 1 4 5 2 3 2 4 5
Germany India Turkey Russia Germany Turkey Germany Germany Russia Russia
1 4 2 4 4 3 1 0 5 0
Turkey France India France Germany Russia Russia Russia India Turkey
2 1 5 1 3 1 0 2 3 0
Turkey France India Germany Turkey India France India France Russia
3 2 4 2 3 2 0 3 5 3
India Turkey Germany Germany Turkey Russia Germany Turkey Germany Russia
4 3 2 3 3 4 4 2 3 2
Russia India Turkey Germany India France Russia Russia India France
3 5 5 5 2 1 2 5 2 3
France Russia India India India Turkey France India France India
2 2 4 4 2 4 1 4 0 5
Russia France India India France Turkey France Turkey Turkey Turkey
5 5 4 0 1 3 0 3 3 5
Turkey Turkey India India Russia Germany Turkey Germany France Russia
1 2 4 5 3 0 3 5 0 3
India Germany India India Germany Russia India Russia Russia Russia
5 4 3 5 5 2 5 2 1 3
Germany Russia Germany Turkey India Russia Germany Russia France India
0 0 3 1 2 1 2 3 1 3
France Germany Germany Germany Russia France India Turkey Russia Germany
4 0 4 1 4 4 4 4 5 2

## Example

> names(x2)[x2==0]

## Output

[1] "Germany" "Russia" "Russia" "Turkey" "France" "France" "India"
[8] "France" "Germany" "France" "Germany" "Russia" "Germany"

## Example

> names(x2)[x2==1]

## Output

[1] "Russia" "Germany" "Germany" "France" "France" "Russia" "France"
[8] "France" "France" "Turkey" "Russia" "Turkey" "Russia" "France"
[15] "Germany"

## Example

> names(x2)[x2==2]

## Output

[1] "Germany" "France" "Turkey" "Turkey" "Russia" "France" "Germany"
[8] "India" "Germany" "Turkey" "Russia" "India" "Russia" "India"
[15] "France" "Russia" "India" "Turkey" "Russia" "Russia" "India"
[22] "Germany" "Germany"

## Example

> names(x2)[x2==3]

## Output

[1] "France" "Germany" "Turkey" "Germany" "India" "Turkey" "Turkey"
[8] "India" "Russia" "Turkey" "Germany" "Turkey" "Germany" "Russia"
[15] "France" "Turkey" "Turkey" "Turkey" "Russia" "Turkey" "Russia"
[22] "India" "Russia" "Germany" "Russia" "India"

## Example

> names(x2)[x2==4]

## Output

[1] "Russia" "Turkey" "India" "Russia" "Germany" "India" "India"
[8] "Russia" "Germany" "India" "India" "Turkey" "India" "India"
[15] "India" "Germany" "France" "Germany" "Russia" "France" "India"
[22] "Turkey"

## Example

> names(x2)[x2==5]

## Output

[1] "Russia" "France" "Germany" "Russia" "India" "France" "India"
[8] "Turkey" "Germany" "Russia" "India" "Russia" "France" "Turkey"
[15] "India" "Germany" "India" "India" "Germany" "India" "Russia"

## Example3

Live Demo

> x3<-sample(LETTERS[1:26],100,replace=TRUE)
> x3

## Output

[1] "A" "U" "E" "B" "X" "S" "N" "C" "I" "W" "K" "R" "O" "G" "X" "G" "H" "C"
[19] "G" "M" "M" "U" "O" "C" "C" "N" "W" "O" "W" "C" "B" "D" "L" "P" "W" "M"
[37] "J" "L" "W" "A" "R" "M" "B" "U" "J" "B" "L" "W" "D" "Y" "J" "N" "I" "V"
[55] "J" "S" "Q" "K" "K" "K" "J" "C" "H" "E" "C" "T" "R" "X" "I" "T" "Z" "H"
[73] "E" "I" "Q" "E" "D" "C" "I" "T" "Y" "H" "K" "W" "X" "M" "Y" "E" "Q" "F"
[91] "G" "Q" "Q" "O" "K" "L" "R" "Z" "F" "K"

## Example

> names(x3)<-sample(c("C1","C2","C3","C4","C5"),100,replace=TRUE)
> x3

## Output

C2 C4 C4 C4 C1 C3 C3 C1 C5 C2 C5 C5 C4 C1 C2 C5 C1 C3 C5 C3
"A" "U" "E" "B" "X" "S" "N" "C" "I" "W" "K" "R" "O" "G" "X" "G" "H" "C" "G" "M"
C5 C3 C1 C1 C3 C4 C3 C1 C4 C2 C4 C1 C3 C3 C2 C1 C1 C3 C2 C2
"M" "U" "O" "C" "C" "N" "W" "O" "W" "C" "B" "D" "L" "P" "W" "M" "J" "L" "W" "A"
C1 C2 C4 C1 C5 C1 C5 C1 C1 C3 C3 C1 C3 C1 C3 C4 C5 C1 C3 C3
"R" "M" "B" "U" "J" "B" "L" "W" "D" "Y" "J" "N" "I" "V" "J" "S" "Q" "K" "K" "K"
C2 C1 C1 C5 C1 C3 C5 C1 C2 C1 C4 C5 C3 C1 C4 C4 C5 C3 C4 C5
"J" "C" "H" "E" "C" "T" "R" "X" "I" "T" "Z" "H" "E" "I" "Q" "E" "D" "C" "I" "T"
C2 C4 C4 C4 C1 C5 C5 C1 C3 C2 C4 C2 C4 C1 C1 C1 C2 C3 C5 C5
"Y" "H" "K" "W" "X" "M" "Y" "E" "Q" "F" "G" "Q" "Q" "O" "K" "L" "R" "Z" "F" "K"

## Example

> names(x3)[x3=="A"]

## Output

[1] "C2" "C2"

## Example

> names(x3)[x3=="B"]


## Output

[1] "C4" "C4" "C4" "C1"

## Example

> names(x3)[x3=="C"]

## Output

[1] "C1" "C3" "C1" "C3" "C2" "C1" "C1" "C3"

## Example

> names(x3)[x3=="D"]


## Output

[1] "C1" "C1" "C5"

## Example

> names(x3)[x3=="E"]

## Output

[1] "C4" "C5" "C3" "C4" "C1"

## Example

> names(x3)[x3=="T"]


## Output

[1] "C3" "C1" "C5"

## Example

> names(x3)[x3=="U"]

## Output

[1] "C4" "C3" "C1"

## Example

> names(x3)[x3=="W"]


## Output

[1] "C2" "C3" "C4" "C2" "C2" "C1" "C4"

## Example

> names(x3)[x3=="X"]

## Output

[1] "C1" "C2" "C1" "C1"

## Example

> names(x3)[x3=="Y"]


## Output

[1] "C3" "C2" "C5"

## Example

> names(x3)[x3=="Z"]

## Output

[1] "C4" "C3"

Updated on: 19-Nov-2020

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