title: How to remove Subscripts from the column names of the data table in R?
body: <p>I have some columns in a data frame with column names of CO₂.I want to change this to CO2 (no subscripts). How can I do this? in the data table, it reads as <code>CO2</code> and when I print column names, it reads as CO₂.</p>
  <p>I tried following code but it refuses to change.</p>
  <p><img src="https://i.stack.imgur.com/qQqVN.png" alt="enter image description here" /></p>