R: Remove multiple empty columns of character variables

Question

I have a data frame where all the variables are of character type. Many of the columns are completely empty, i.e. only the variable headers are there, but no values. Is ther

Answer 1

You can do either of the following:

emptycols <- sapply(df, function (k) all(is.na(k)))
df <- df[!emptycols]

or:

emptycols <- colSums(is.na(df)) == nrow(df)
df <- df[!emptycols]

If by empty you mean they are "", the second approach can be adapted like so:

emptycols <- colSums(df == "") == nrow(df)