The dictionary data type

In [1]:

    

myCat = {'size': 'fat', 'color':'gray', 'disposition':'loud'}


    

In [2]:

    

myCat['size']


    

    
Out[2]:





'fat'

In [3]:

    

'My cat has ' + myCat['color'] + ' fur.'


    

    
Out[3]:





'My cat has gray fur.'

In [4]:

    

spam = {12345: 'Luggage Combination', 42: 'The Answer'}


    

In [5]:

    

spam = ['cats', 'dogs', 'moose']


    

In [6]:

    

bacon = ['dogs', 'moose', 'cats']


    

In [7]:

    

spam == bacon


    

    
Out[7]:





False

In [8]:

    

eggs = {'name': 'Zophies', 'species': 'cat', 'age': 8}


    

In [9]:

    

ham = {'species': 'cat', 'age': 8, 'name': 'Zophies'}


    

In [10]:

    

eggs == ham


    

    
Out[10]:





True

In [11]:

    

spam['color']


    

    




---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-11-4ab2633f52b0> in <module>()
----> 1 spam['color']

TypeError: list indices must be integers or slices, not str

In [12]:

    

spam = {'color': 'red', 'age': 42}


    

In [13]:

    

for v in spam.values():
    print(v)


    

    




red
42

In [14]:

    

for k in spam.keys():
    print(k)


    

    




color
age

In [15]:

    

for i in spam.items():
    print(i)


    

    




('color', 'red')
('age', 42)

In [16]:

    

spam.keys()


    

    
Out[16]:





dict_keys(['color', 'age'])

In [17]:

    

list(spam.keys())


    

    
Out[17]:





['color', 'age']

In [18]:

    

for k, v in spam.items():
    print('Key: ' + k + ', Value: ' + str(v))


    

    




Key: color, Value: red
Key: age, Value: 42

In [19]:

    

spam = {'name': 'Zophie', 'age': 7}


    

In [20]:

    

'name' in spam.keys()


    

    
Out[20]:





True

In [21]:

    

'Zophie' in spam.values()


    

    
Out[21]:





True

In [22]:

    

'color' in spam


    

    
Out[22]:





False

In [23]:

    

'color' not in spam.keys()


    

    
Out[23]:





True

In [25]:

    

'color' in spam.keys()


    

    
Out[25]:





False

In [26]:

    

picnicItems = {'apples': 5, 'cups': 2}


    

In [27]:

    

'I am bringing ' + str(picnicItems.get('cups', 0)) + ' cups.'


    

    
Out[27]:





'I am bringing 2 cups.'

In [28]:

    

'I am bringing ' + str(picnicItems.get('eggs', 0)) + ' eggs.'


    

    
Out[28]:





'I am bringing 0 eggs.'

In [29]:

    

'I am bringing ' + str(picnicItems['eggs']) + ' eggs.'


    

    




---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-29-b435afff13bf> in <module>()
----> 1 'I am bringing ' + str(picnicItems['eggs']) + ' eggs.'

KeyError: 'eggs'

In [30]:

    

spam = {'name': 'Pooka', 'age': 5}


    

In [31]:

    

if 'color' not in spam:
    spam['color'] = 'black'


    

In [32]:

    

spam


    

    
Out[32]:





{'age': 5, 'color': 'black', 'name': 'Pooka'}

In [36]:

    

spam = {'name': 'Pooka', 'age': 5}


    

In [34]:

    

spam.setdefault('color', 'black')


    

    
Out[34]:





'black'

In [35]:

    

spam


    

    
Out[35]:





{'age': 5, 'color': 'black', 'name': 'Pooka'}

In [ ]: