How to Create Data Frame in R: Syntax and Examples

In R, you create a data frame using the data.frame() function by passing vectors of equal length as columns. Each vector becomes a column, and the function combines them into a table-like structure called a data frame.

Syntax

The basic syntax to create a data frame is data.frame(column1 = vector1, column2 = vector2, ...). Each argument defines a column name and its values as a vector. All vectors must have the same length to form rows.

r

data.frame(column1 = c(value1, value2), column2 = c(value3, value4))

Example

This example creates a data frame with three columns: Name, Age, and City. It shows how to combine character and numeric vectors into a data frame.

r

df <- data.frame(
  Name = c("Alice", "Bob", "Charlie"),
  Age = c(25, 30, 35),
  City = c("New York", "Los Angeles", "Chicago")
)
print(df)

Output

     Name Age         City
1   Alice  25     New York
2     Bob  30  Los Angeles
3 Charlie  35      Chicago

Common Pitfalls

Common mistakes include using vectors of different lengths, which causes an error, or forgetting to name columns, which results in default names like X1, X2. Also, mixing data types in a single vector can cause unexpected behavior.

r

## Wrong: vectors of different lengths
# data.frame(Name = c("Alice", "Bob"), Age = c(25))

## Right: vectors of equal length
data.frame(Name = c("Alice", "Bob"), Age = c(25, 30))

Quick Reference

Function	Description
data.frame()	Creates a data frame from vectors
c()	Combines values into a vector
print()	Displays the data frame content

Key Takeaways

Use data.frame() with vectors of equal length to create a data frame.

Name each vector argument to set column names clearly.

Mixing data types in one vector can cause issues; keep columns consistent.

Always check vector lengths to avoid errors when creating data frames.