what is assumed is ,you want the date format in today's date format.
if that is the scenario.
first we have to tell qlikview about how the date format is there for the field.
Ex: 02 February 2017
date#(Datefield,'DD MMM YYYY')
and now we have get desired date format(for suppose your desired format is 'DD-MM-YYYY',27-03-2017)
date(date#(Datefield,'DD MMM YYYY'),'DD-MM-YYYY')
hope i make the point.
please let me know anything you didnt get it