Deleting multiple columns in R

Question

I have a dataframe df with column names from m1 to m100

I want to delete columns in the range m50 to m100. Is there a faster way to do it than hardcoding it

Answer 1

We can assign the columns to NULL in data.table

library(data.table)
setDT(df_cohort)[, paste0('M', 50:100) := NULL]

If we need to subset,

setDT(df_cohort)[, setdiff(names(df_cohort), 
                    paste0('m', 50:100)), with=FALSE]