title: Undo A Change in RStudio
body: <p>I'm not sure this is possible, but I accidentally changed data within my data.csv file by writing the wrong command (i.e.- I replaced certain random text with NAs).  Is there a way to simply "undo" that change in the file (i.e.- recover the original text) or do I need to re-upload my original data.csv file and start over again?</p>