👀 Views: 73 💬 Answers: 1 📅 Created: 2025-06-12

r dataframe merge R

I tried several approaches but none seem to work. I've been working on this all day and I'm performance testing and I'm stuck on something that should probably be simple. I'm a bit lost with I'm working with an scenario when trying to merge two data frames using the `merge` function in R 4.3. My intention is to combine `df1` and `df2` based on different column names, but I'm getting unexpected NA values in the resulting data frame. Here's the code that I'm using: ```r # Sample data frames df1 <- data.frame(ID_A = 1:5, Value_A = letters[1:5]) df2 <- data.frame(ID_B = 3:7, Value_B = LETTERS[1:5]) # Merging data frames with different column names result <- merge(df1, df2, by.x = "ID_A", by.y = "ID_B", all = TRUE) ``` The output I expected was a data frame that shows all rows from both `df1` and `df2`, but instead, I see a lot of NA values where I expected data. The resulting data frame looks like this: ``` ID_A Value_A ID_B Value_B 1 1 a <NA> <NA> 2 2 b <NA> <NA> 3 3 c 3 A 4 4 d <NA> <NA> 5 5 e <NA> <NA> 6 <NA> <NA> 4 B 7 <NA> <NA> 5 C 8 <NA> <NA> 6 D 9 <NA> <NA> 7 E ``` I've tried using `all.x = TRUE` and `all.y = TRUE`, but that didn't change the outcome. I also double-checked the types of the ID columns, and they're both integers, so that shouldn't be an scenario. Any suggestions on how to resolve this or understand why I'm getting these NA values? Am I using the merge function incorrectly? The project is a desktop app built with R. What are your experiences with this? This issue appeared after updating to R 3.9. What's the best practice here? I'm working in a Windows 11 environment. Has anyone dealt with something similar? This is part of a larger service I'm building. Has anyone dealt with something similar? I'm developing on Ubuntu 20.04 with R. Any help would be greatly appreciated!