What is that PHP error?

When I go to my site, it wrote:

Fatal error: Call to undefined function: formatted_table_tops() in /home/.walden/vmsource/vm-source.com/login.php on line 15

What’s that mean?

Is the path to my domain is: home/username/domain??


I think a file is missing/not included in your management package.
formatted_table_tops is not a default PHP function so it must be one created by your software, that is missing for some reason.