Welcome to CS1315. Click on the python to add comments. Looking for the book? They have it at the Engineer's Bookstore at 748 Marietta St NW. Here is there website: http://www.engrbookstore.com/ - Monica
	Hotspots: Slides and Code • TA Corner • Comments? • Announcements • FAQ • Static Webspace

Midterm Exam 2 Review Fall 2003: Duplicate a List

Answers? Comments? Questions on Answers? Questions on Comments?

def duplicateList(list):
  duplicteList = []
  i = 0
  for item in list[:]:
    duplicateList[i] = item
    duplicateList[i+1] = item
    index = i + 2
  print duplicateList
  return duplicateList

def duplicateList(list):
  duplicateList = []
  for entry in list:
    duplicateList.append(entry)
    duplicateList.append(entry)
  print duplicateList

 tags.



See the FAQ page.  Do you see why you got that error on the first one?  When you duplicate the elements, you end up with twice as many elements.  You can't make a list longer by referring to indices that don't exist yet. Mark Guzdial




will someone walk through this code and explain why it works?  I don't understand what "duplicateList.append(entry)" is doing.


would this work also?



def duplicateList(list):

newlist = []

  for item in list:

    newlist = newlist + [item]+[item]

return newlist   





list.append(something) puts something at the end of the list.  So if the list were ["a","b","c"], doing list.append["d"] would give you ["a","b","c","d"] in the list. Mark Guzdial




Within the above programs the line: newlist = []

This is opening a new list, right?



It's setting "newlist" to an empty list, yes. Mark Guzdial





Link to this Page

Fall2003 Midterm Review 2 last edited on 21 October 2003 at 11:43 am by w205d210.lawn.gatech.edu