hi
I have a dataset based upon spells in hospitals and the wards stayed on during that stay
spell_id , id , ward , spell_start , spell end , ward_start , ward end
1200 , 1 , red ,01/02/2015 , 31/04/2015 ,01/02/2015 , 21/02/2015
1200 , 2 , red ,01/02/2015 , 31/04/2015 ,22/02/2015...