I'm new to coding and am figuring out most things OK, but

Hi,

I'm new to coding and am figuring out most things OK, but I'm stuck trying to filter the BP 1.9 activity feed to display only posts/updates from members. All the documentation I have come across have mentioned editing code in the activity-loop.php file.

I can't find the .php file anywhere, it's not in the plugins folder... Can someone please help either by sharing a code that would work or pointing me to the right file to edit?