R Basic

How to Create a Data Frame from Vectors in R

In R, you can think of a vector as a series of values in a single column. It contains the same data type. Each column of a data frame is a vector. So, if I have several vectors, I can combine them and create a data frame out of them.

To create a data frame from vectors in R, use the data.frame() function and pass the vectors. Ensure you have the same length of all the vectors; otherwise, R throws an error.

After the data frame has been created, each column retains its data type.

Basic Data Frame Creation

The above figure shows five vectors. Each vector has its own type and the same length, which is five. After converting vectors to a data frame, each vector becomes a column of the data frame.

title <- c("Inception", "The Dark Knight", "Interstellar", "The Matrix", "Gladiator")
genre <- c("Sci-Fi", "Action", "Sci-Fi", "Sci-Fi", "Drama")
year <- c(2010, 2008, 2014, 1999, 2000)
rating <- c(8.8, 9.0, 8.6, 8.7, 8.5)
runtime <- c(148, 152, 169, 136, 155)


# Create a data frame from vectors
df <- data.frame(title, genre, year, rating, runtime)

print(df)

Output

Displaying the internal structure of the data frame

If you want to implement the internal structure of the data frame, you can use the “str()” function and pass the data frame to it.

title <- c("Inception", "The Dark Knight", "Interstellar", "The Matrix", "Gladiator")
genre <- c("Sci-Fi", "Action", "Sci-Fi", "Sci-Fi", "Drama")
year <- c(2010, 2008, 2014, 1999, 2000)
rating <- c(8.8, 9.0, 8.6, 8.7, 8.5)
runtime <- c(148, 152, 169, 136, 155)


# Create a data frame from vectors
df <- data.frame(title, genre, year, rating, runtime)

# Printing data frame structure
str(df)

Output

The above screenshot shows that title, genre have character columns, and year, rating, runtime have numeric columns.

Adding a new column to an existing data frame

To add a column to an existing data frame, you can use the “$” operator and assign values to the new column.

Let’s add the “director” column to our data frame.

title <- c("Inception", "The Dark Knight", "Interstellar", "The Matrix", "Gladiator")
genre <- c("Sci-Fi", "Action", "Sci-Fi", "Sci-Fi", "Drama")
year <- c(2010, 2008, 2014, 1999, 2000)
rating <- c(8.8, 9.0, 8.6, 8.7, 8.5)
runtime <- c(148, 152, 169, 136, 155)


# Create a data frame from vectors
df <- data.frame(title, genre, year, rating, runtime)

# Adding a new column to an existing data Frame
df$director <- c("C Nolan", "C Nolan", "C Nolan", "L Wachowski", "R Scott")
print(df)

Output

Adding a new row to an existing data frame

You can add a new row to an existing data frame using the rbind() function. It accepts the first argument as an existing data frame and a vector that will become a new row in the data frame.

title <- c("Inception", "The Dark Knight", "Interstellar", "The Matrix", "Gladiator")
genre <- c("Sci-Fi", "Action", "Sci-Fi", "Sci-Fi", "Drama")
year <- c(2010, 2008, 2014, 1999, 2000)
rating <- c(8.8, 9.0, 8.6, 8.7, 8.5)
runtime <- c(148, 152, 169, 136, 155)

# Create a data frame from vectors
df <- data.frame(title, genre, year, rating, runtime)

# Adding a row to an existing data frame
df <- rbind(df, c("Kaun", "Horror", 1999, 7.8, 134))
print(df)

Output

That’s it!

Recent Posts

How to Set and Get Working Directory [setwd() and getwd()] in R

Set the current working directory The setwd() function sets the working directory to the new…

3 days ago

Standard deviation in R [Using sd() Function]

The sd() function in R calculates the sample standard deviation of a numeric vector or…

4 days ago

R dnorm(): Probability Density Function

The dnorm() function in R calculates the value of the probability density function (pdf) of…

5 days ago

R rep() Function: Repeating Elements of a Vector

R rep() is a generic function that replicates elements of vectors and lists for a…

1 week ago

Splitting Strings: A Beginner’s Guide to strsplit() in R

The strsplit() function in R splits elements of a character vector into a list of…

1 week ago

Understanding of rnorm() Function in R

The rnorm() method in R generates random numbers from a normal (Gaussian) distribution, which is…

2 weeks ago