William Verrett

I have a series of data 56 days(5/13 to 7/8) long that represents one interval of shifts at a plant (4 shifts on a 2-3-3-3 schedule). I want to create a signal that is basically that interval of data repeated forever in either direction. The idea would be to be able to use that signal to determine what shift is on at any given time and compare data across shifts. How would I make this 56 day signal into something continuous? Thanks in advance!