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Beginning Python: Data Types

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Lists

Assigning Values to a List

A list is, as the name suggests, a series of values. In Python, these values are assigned by placing them within square braces and separating them by commas like this:

 <name of list> = [ <value>, <value>, <value> ] 
 girls = ['sugar', 'spice', 'everything nice'] 
 lotto = ['26', '12', '23'] 
 addends = [4, 34, 7] 
 
Note that 'addends' is comprised of integer variables while the others are comprised of strings, as the quotes suggest.

A list can contain any type of Python object -- even other lists.
 >>> lotto[2] = addends 
 >>> print lotto 
 ['26', '12', [4, 34, 7]] 
 

Accessing the Values of List

To access a part of a list, one uses the same kind of phrase as one used for a string literal:

 <name of list>[<index number>] 
A few examples:
 ingredient1 = girls[0] 
 print girls[1] 
 print 'brown ' + ingredient1 
 print girls[0] + " is not a " + girls[1] 
output:
spice
brown sugar
sugar is not a spice

Combining Lists

Lists can be concatenated in a way similar to strings by using the plus operator ('+'):

 primes = [1, 3, 5, 7] + [9, 11] 
 mishmash = girls + lotto + addends 
 print primes 
 print mishmash 
output:
[1, 3, 5, 7, 9, 11]
['sugar', 'spice', 'everything nice', '26', '12', '23', 4, 34, 7]
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