groupBy dates in descending order

Hi, new to Kirby and usually more focused on the graphic design side of things. Next to no php experience, so I apologize for this very, very basic question.

I’m using Kirby to make a blog and trying to group posts on the main page by date using groupBy to show the date on posts once per day. This was suggested in this post, and I’ve more or less borrowed the code from the docs on the function.

Using the code there, groupBy() is returning entries in ascending order, and I’d like it to return dates by descending order. Is there a method by which I can make this happen?

Thank you very much in advance!

EDIT: Figured it out, thanks. flip()