Capitalizing text of a specific column in R's data frame

Question

I have a data that looks like this:

GO:2000974 7,8 negative_regulation_of_pro-B_cell_differentiation Notch1 ISS
GO:2000974 7,8 negative_regulation_of_pro-B_c         


        

Answer 1

Just use the toupper function:

R> toupper(c("a", "ab"))
[1] "A"  "AB"

For your data frame, you will have:

dat[,4] = toupper(dat[,4])