R is one of the most popular and powerful programming languages used in data analytics.
If you already have your data located in a CSV file or Excel file, you can follow the steps in these tutorials to import it into R:
- How to Import CSV Files into R
- How to Import Excel Files into R
However, sometimes you may want to manually enter raw data into R. Let see how to do it
Entering a Vector in R
If you want to enter a single vector of numeric values into R, use the following syntax:
#create vector of numbers #Method 1 >numbers <- (1:25) #Method 2 >even <- c(2,4,6,8,10) #display class of vector >class(numbers) [1] "integer" >class(even) [1] "numeric" #display vector of numeric values >numbers [1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 >even [1] 2 4 6 8 10 #return fifth element in vector numbers[5] [1] 5 >even[5] [1] 10
Use the same syntax to enter a vector of character values as well
#create vector of character values
metal <- c("iron", "silver", "gold", "steel")
#display class of vector
>class(metal)
[1] "character"
#display vector of character values
>metal
[1] "iron" "silver" "gold" "steel"
Entering a DATAFRAME in R
If you want to create a data frame use the following syntax
#create data frame
>football_players <- data.frame(player=c("Salah", "Jesus", "Ozil", "Pepe", "Kane"),
goals=c(15, 10, 8, 10, 16),
assists=c(4, 7, 10, 4, 5))
#display data frame
>football_players
player goals assists
1 Salah 15 4
2 Jesus 10 7
3 Ozil 8 10
4 Pepe 10 4
5 Kane 16 5
#display class of df
>class(football_players)
[1] "data.frame"
#return value in third row and second column
>football_players[3,2]
[1] 8
Entering a Matrix in R
If you want to create a matrix use the following syntax
#create matrix with two columns and five rows
>goals=c(15, 10, 8, 10, 16)
>assists=c(4, 7, 10, 4, 5)
#column bind the two vectors together to create a matrix
>mat <- cbind(goals, assists)
#display matrix
>mat
goals assists
[1,] 15 4
[2,] 10 7
[3,] 8 10
[4,] 10 4
[5,] 16 5
#display class of mat
>class(mat)
[1] "matrix" "array"
#return value in fourth row and second column
>mat[4, 2]
assists
4
Note: A matrix requires each column to be the same type, unlike data frames.
You learn more about Data analysis using R here.