Question
i have recently found feces (tubular, approx 1/2 inch long)in and all around my cat litter box on the patio. is this probably a squirrel, or rat or ?  i have moved the box inside.   thanx

Answer
I would suspect rat more than squirrel. But much more information is needed for a positive id.

Visit http://icwdm.org/Inspection/droppingfeces.asp  to learn about the complexities of scat identification

I would also strongly suggest that you keep your cat indoors. Outdoor cats bring things to you that you won't want, ie. diseases.