How to Generate a Sample Using the Sample Function in R? (original) (raw)

Last Updated : 23 Jul, 2025

In this article, we will discuss how to generate a sample using the sample function in R.

Sample() function is used to generate the random elements from the given data with or without replacement.

Syntax:

sample(data, size, replace = FALSE, prob = NULL)

where,

• data can be a vector or a dataframe
• size represents the size of the sample
• replace is used to set the values again repeated if it is set to true
• prob: a vector of probability weights for obtaining the elements of the vector being sampled

Example 1: Generate sample data from the vector

Here, we will generate the n sample data from the given vector with 11 elements using the sample function.

R `

consider the vector

data=c(23,45,21,34,5,6,7,8,86,45,3)

get 4 random elements

print(sample(data,4))

get 1 random element

print(sample(data,1))

get 6 random elements

print(sample(data,6))

`

Output:

[1] 45 7 5 34 [1] 3 [1] 5 23 8 21 6 45

Example 2: Generate sample data from the vector by replacing

Here we are going to create a vector with 11 elements and generate the sample data with a replacement.

R `

consider the vector

data=c(23,45,21,34,5,6,7,8,86,45,3)

get 4 random elements

print(sample(data,4,replace=TRUE))

get 1 random element

print(sample(data,1,replace=TRUE))

get 6 random elements

print(sample(data,6,replace=TRUE))

`

Output:

[1] 45 5 5 3 [1] 86 [1] 5 5 8 7 8 45

Example 3: Sampling with Uneven Probabilities Using sample Function

Here we are going to select the elements with higher probability than others by setting the probability using the prob parameter.

R `

consider the vector

data=c(23,45,21,34,5)

get 10 random elements with probability

print(sample(data, size = 10, replace = TRUE, prob = c(0.6,0.1,0.1,0.1,0.1)))

`

Output:

[1] 23 23 23 23 23 45 23 23 23 23

Example 4: Random Sampling of Data Frame Rows Using sample Function

Here we are going to sample the dataframe, let us create a dataframe and sample the rows.

R `

create dataframe with 2 columns

data=data.frame(col1=c(1:10),col2=c(12:21))

get the sample of 4 in each column

data[sample(1:nrow(data), size = 4), ]

`

Output:

Example 5: Random Sampling of List Elements Using sample Function

Here we are going to sample the data in the list with size 4

R `

create list with some integers

data=list(1,2,3,4,5,6)

get the sample of 4

data[sample(1:length(data), size = 4)]

`

Output:

[[1]] [1] 2

[[2]] [1] 1

[[3]] [1] 4

[[4]] [1] 6