How to change column names of a data frame in R?
If you have a data frame df
and want to rename all columns, you can do:
names(df) <- c("new_name1", "new_name2", "new_name3")
Ensure you have exactly as many new names as there are columns in df
.
Using colnames()
colnames()
is functionally similar to names()
for data frames. For instance:
colnames(df) <- c("colA", "colB", "colC")
Either approach gives the same result.
Using dplyr::rename()
If you only need to rename some columns or prefer a pipe-friendly syntax:
library(dplyr) df <- df %>% rename( new_col_name1 = old_col_name1, new_col_name2 = old_col_name2 )
rename()
maps new_name = old_name
. You don’t need to rename every column at once; only specify those that need changes.
Pro Tips
- Validate you’re not introducing duplicate names.
- Always check your data after renaming to avoid referencing old column names in subsequent code.
Further Skill-Building
If you’d like to polish your data manipulation and interview problem-solving skills, consider:
- Grokking the Coding Interview: Patterns for Coding Questions
- Grokking Data Structures & Algorithms for Coding Interviews
For designing scalable and efficient systems, explore Grokking System Design Fundamentals. Get personalized feedback through Coding Mock Interviews, led by ex-FAANG engineers, and check out the DesignGurus.io YouTube channel for quick, insightful tutorials.