Explain Dictionary method in Phytons.
Answers
Answer:
Python Dictionary Methods.
Method Description
fromkeys() Returns a dictionary with the specified keys and value
get() Returns the value of the specified key
items() Returns a list containing a tuple for each key value pair
keys() Returns a list containing the dictionary's keys
Dictionary Methods
The dict class provides various methods using which we can perform a variety of operations. In addition to these methods, we can use built-in len() functions to get the length of a dictionary.
In []: len(ticker)
Out[]: 5
In []: len(tickers)
Out[]: 2
◘ Some of the popular methods provided by the dict class :
• items() : This method returns an object containing all items in the calling object. That is, it returns a list of tuples containing keys and values.
In []: ticker.items()
Out[]: dict_items([('symbol', 'AAPL'), ('price', 226),
('company', 'Apple Inc'),
('founded', 1976),
('products', ['Machintosh', 'iPod',
'iPhone', 'iPad']])
____________________
• keys() : This method returns all keys in the calling dictionary.
In []: ticker.keys()
Out[]: dict_keys(['symbol', 'price', 'company', 'founded',
'products'])
____________________
• values() : This method returns all values in the calling object.
In []: ticker.values()
Out[]: dict_values(['AAPL', 224.95, 'Apple Inc', 1976,
['Machintosh', 'iPod', 'iPhone',
'iPad']])
____________________
• pop() : This method pops the item whose key is given as an argument.
In []: tickers
Out[]:
{'GOOG': 'Alphabet Inc.',
'AAPL': 'Apple Inc.',
'MSFT': 'Microsoft Corporation'}
In []: tickers.pop('GOOG')
Out[]: 'Alphabet Inc.'
In []: tickers
Out[]: {'AAPL': 'Apple Inc.',
'MSFT': 'Microsoft Corporation'}
____________________
• copy() : As the name suggests, this method copies the calling dictionary to another dictionary.
In []: aapl = ticker.copy()
In []: aapl
Out[]:
{'symbol': 'AAPL',
'price': 224.95,
'company': 'Apple Inc',
'founded': 1976,
'products': ['Machintosh', 'iPod', 'iPhone', 'iPad']}
____________________
• clear() : This method empties the calling dictionary.
In []: ticker.clear()
In []: ticker
Out[]: {}
____________________
• update() : This method allows to add new key-pair value from another dictionary.
In []: ticker1 = {'NFLX' : 'Netflix'}
In []: ticker2 = {'AMZN' : 'Amazon'}
In []: new_tickers = {}
In []: new_tickers.update(ticker1)
In []: new_tickers.update(ticker2)
In []: new_tickers
Out[]: {'NFLX': 'Netflix', 'AMZN': 'Amazon'}b