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Basic Datatypes: Lists

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This is the most important datatype in Python, this is what you'll use the most. It's a dynamic array actually.

list = []   # empty list

li = ['vader', 'luke', 'boba', 'jabba', 'yoda']
print len(li)   # 5
print li[-1]   # yoda
print li[1:3]   # luke, boba (3-1=2, i.e. this slice has 2 elems). The end index is EXCLUSIVE.
print li[0:-1]   # vader, luke, boba, jabba (everything, except the last elem)

# slicing shorthand
print li[:3]   # vader, luke, boba
print li[3:]   # jabba, yoda
print li[:]    # a complete copy of li (this is a different list!)

li.remove('yoda')    # vader, luke, boba, jabba
li.append('jabba')   # vader, luke, boba, jabba, jabba
li.remove('jabba')   # removes the FIRST occurrence only
print li   # ['vader', 'luke', 'boba', 'jabba']

li.insert(1, 'solo')   # insert 'solo' BEFORE the elem at position 1, i.e. before 'luke'
print li   # ['vader', 'solo', 'luke', 'boba', 'jabba']

li.extend(['a', 'b', 'c'])   # extend has 1 argument, which is ALWAYS a list
print li   # ['vader', 'solo', 'luke', 'boba', 'jabba', 'a', 'b', 'c']
li.append(['d', 'e'])   # insert one element, a list, i.e. the last elem will be a nested list
print li   # ['vader', 'solo', 'luke', 'boba', 'jabba', 'a', 'b', 'c', ['d', 'e']]

print li.index('boba')   # 3 (finds the FIRST occurrence)
print 'vader' in li   # True
print 'yoda' in li   # False

lastElem = li.pop()   # remove the last elem and return it
print lastElem   # ['d', 'e']
print li         # ['vader', 'solo', 'luke', 'boba', 'jabba', 'a', 'b', 'c']

li = ['a', 'b']
li += ['c', 'd']   # like extend()
print li   # ['a', 'b', 'c', 'd']
li = li + ['x', 'y']   # SLOW! Returns a NEW list while extend() alters an existing list IN PLACE.

li = [3, 5] * 3
print li   # [3, 5, 3, 5, 3, 5]

Some List Functions