Operators and Built-in Functions

Name: Operators and Built-in Functions
Uploaded: 2019-09-03T14:00:00+00:00
Duration: 5 min 21 s
Description: Operators and Built-in Functions

Course: Lists and Tuples in Python
Chris Bailey 05:21 0 Comments

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In this lesson, you’ll see how operators and Python’s built-in functions can be applied to lists. Several Python operators can be used with lists. in and not in are membership operators and can be used with lists. A membership operator used on a list:

Returns True if the first operand is contained within the second
Returns False otherwise
Can also be used as not in

Here’s an example:

>>>

>>> a = ['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']
>>> a
['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']

>>> 'spam' in a
True
>>> 'egg' in a
True
>>> 'kiwi' in a
False
>>> 'kiwi' not in a
True

Here’swhat happens with the concatenation (+) and replication (*) operators:

The concatenation (+) operator concatenates the operands.
The replication (*) operator creates multiple concatenated copies.

Here’s an example:

>>>

>>> a 
['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']

>>> a + ['kiwi', 'mango']
['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster', 'kiwi', 'mango']

>>> a
['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']
>>> a * 2
['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster', 'spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']
>>> 2 * a
['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster', 'spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']

Several Python built-in functions can also be used with lists:

len() returns the length of the list.
min() returns the object from the list with the smallest value.
max() returns the object from the list with the highest value.

Here’s an example:

>>>

>>> a = ['spam', 'egg', 'bacon', 'tomato', 'ham', 'lobster']
>>> len(a)
6
>>> b = [4, 99, 55, 23, 5, 6]
>>> b
[4, 99, 55, 23, 5, 6]
>>> len(b)
6
>>> min(b)
4
>>> max(b)
99

>>> min(a)
'bacon'
>>> max(a)
'tomato'

>>> c = ['apple', 'bacon', 'Asparagus', 'Zebra']
>>> c
['apple', 'bacon', 'Asparagus', 'Zebra']
>>> min(c)
'Asparagus'
>>> max(c)
'bacon'

>>> ord('A')
65
>>> ord('a')
97
>>> ord('z')
122
>>> ord('Z')
90
>>> max(c)
'bacon'

>>> d = [2, 3, 5, 8, 'apple', 'bacon', 'spam']
>>> len(d)
7
>>> min(d)
Traceback (most recent call last):
  File "<input>", line 1, in <module>
    min(d)
TypeError: '<' not supported between instances of 'str' and 'int'

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