title: R: How to convert factors into numeric for a DATA FRAME?
body: <p>I want to convert factors into numeric. I know this a FAQ, I tried already <code>as.numeric(levels(f))[f]</code> and <code>as.numeric(as.character(f))</code>. But this doesn't help as I want to convert all columns (more than 1000 and all of type factor) of the df into numeric. How can I do this? </p>