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→Dictionary
==== Tuple ====
==== Tuple ====
==== Dictionary ====
==== Dictionary ====
Key - Value pairs,
Key - Value pairs. They are called diferent in diferent languages:<br />
dictionary[key] = value <br />
* Perl → Associative arrays
* Java → Properties, Map or HashMap
* C# → Property bag
<br />
Declarationn and assigment:<br />
There are two posible ways to declare them:
* purse = dict()
* puse = {}
<source lang="python">
purse = dict()
purse['money'] = 12
purse['candy'] = 3
print purse['money']
</source>
purse = {'money': 12, 'candy' = 3}<br />
'''get() method:'''<br />
If you try to retrieve a value for a key that doesn't exist you would get a traceback error.<br />
To avoid this you should use the get() method, that returns the default value if the key doesn't exist:
purse.get(name, default_value)
'''Other methods and functions'''<br />
* list(purse) → Returns a list of keys.
* dict.keys() → Returns a list of keys.
* dict.values() → Returns a list of values.
* dict.items → Returns a list of tuples ( [(key, value), (key, value)...] )
''' Word count using files and dictionarys'''<br />
<source lang="python">
<source lang="python">
counts = dict()
file_path = raw_input('Enter file name: ')
file_handle = open(file_path, 'r')
text = file_handle.read()
words = text.split()
for word in words:
counts[word] = counts.get(word, 0) + 1
bigCount = None
bigWord = None
for word, count in counts.items():
if bigCount is None or count > bigCount:
bigWord = word
bigCount = count
print 'Most frequent word: ', bigWord, '\nFrequency: ', bigCount'
</source>
</source>