Because reduce doesn't do what you want. You'd want "all". L1 = [1,2,3] L2 = ["A1","B2","C3",1,2,3] print all((x in L2 for x in L1)) # prints True L3 = ["A1","B2","C3"] print all((x in L2 for x in L3)) # prints True
----- Original Message ----- From: Asim <asim....@gmail.com> To: python-list@python.org Cc: Sent: Saturday, January 5, 2013 7:25 PM Subject: reduce expression to test sublist Hi All The following reduce expression checks if every element of list lst1 is present in list lst2. It works as expected for integer lists but for lists of strings, it always returns False. reduce( lambda x,y: (x in lst2) and (y in lst2), lst1) Moreover, for the lists of strings the following for-loop gives correct results when the above reduce expression doesn't. isSublist = True for i in lst1: isSublist = isSublist and (i in lst2) if not isSublist: isSublist = False break Can someone help me understand why? Asim -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
