PHP Formula for IPB Forum?

[Padgoi]

I'm looking to create a formula that would calculate karma for users.  Basically I would want the formula to add one karma point for every day a user logs in to the forums.  If the user does not log into the forums, then they don't get a karma point.  I'm pretty sure there is some type of built-in function for the forums that would make this easier, but not sure.

 

Right now, here's what I do know:

 

$member['stats'] =  (((time() - $member['joined']) / 86400), 0);

 

I know this code would calculate how many total days the user has been registered at the forums, but I want it so it only adds a point for when the user logs in to the forums.  Any help would really be appreciated.