Hey there, fellow data enthusiasts! As a Stata user, I recently found myself in need of an equivalent to the collapse command in R. I had budget data by line item, and department was a categorical variable. I wanted to sum it up at the department level.
After some digging, I discovered that R has a few ways to achieve this. One approach is to use the aggregate function, which allows you to summarize data by one or more variables. For example, if your data is in a dataframe called ‘df’, you could use the following code:
`aggregate(df$amount ~ df$department, FUN = sum)`
This would give you the sum of ‘amount’ for each unique value in the ‘department’ column.
Another option is to use the dplyr package, which provides a more intuitive and flexible way to manipulate data. With dplyr, you could use the group_by and summarise functions to achieve the same result:
`library(dplyr)`
`df %>% group_by(department) %>% summarise(total_amount = sum(amount))`
Both of these approaches should give you the desired outcome. But I’m curious – are there any other ways to collapse data in R that I might have missed?
Share your thoughts and experiences in the comments!