R Language Interview Questions and Answers
Test your skills through the online practice test: R Language Quiz Online Practice Test
Ques 6. Explain the use of the 'apply()' function in R.
The apply() function is used to apply a function to the rows or columns of a matrix or array.
Example:
apply(matrix, 1, sum)
Is it helpful?
Add Comment
View Comments
Ques 7. What is the purpose of the 'merge()' function in R?
The merge() function is used to merge two or more data frames based on a common column.
Example:
merged_data <- merge(df1, df2, by='common_column')
Is it helpful?
Add Comment
View Comments
Ques 8. Explain the concept of factor variables in R.
Factor variables are used to represent categorical data in R. They can have levels, which represent the categories.
Example:
gender <- factor(c('Male', 'Female', 'Male'), levels=c('Male', 'Female'))
Is it helpful?
Add Comment
View Comments
Ques 9. How do you handle missing values in a data frame in R?
You can use the na.omit() function to remove rows with missing values, or use functions like is.na() to identify missing values.
Example:
cleaned_data <- na.omit(df)
Is it helpful?
Add Comment
View Comments
Ques 10. Explain the purpose of the 'dplyr' package in R.
The 'dplyr' package provides a grammar of data manipulation, with functions like filter(), select(), and mutate(), making data manipulation tasks more intuitive.
Example:
library(dplyr)
filtered_data <- filter(df, Age > 25)
Is it helpful?
Add Comment
View Comments
Most helpful rated by users: