Python’s efficient key/value hash table structure is called a “dictionary” or “dict”. Major difference between list and dictionary is that index is always numeric in list whereas in dictionary it can be of any data type.The contents of a dict can be written as a series of key:value pairs within braces { }, e.g. dict = {key1:value1, key2:value2, … }. The “empty dict” is just an empty pair of curly braces {}.
>>> dict={} >>> dict {} >>> dict['a']="blue" >>> dict['b']="sky" >>> dict['c']="earth" >>> dict {'a': 'blue', 'b': 'sky', 'c': 'earth'} >>> dict['a'] 'blue' >>> type(dict) <class 'dict'> >>> dict={'a':'sky','b':'blue'} #other way to create dictionary >>> dict {'a': 'sky', 'b': 'blue'}
How to display key and values
>>> for k, v in dict.items(): print(k,'>',v) ... a > blue b > sky c > earth >>> for a in dict.values(): print(a) ... blue sky earth >>> for b in dict.keys(): print(b) ... a b c
changing values and removing values
>>> dict {'a': 'blue', 'b': 'sky', 'c': 'earth'} >>> dict['a']="black" >>> dict {'a': 'black', 'b': 'sky', 'c': 'earth'} >>> dict.pop('a') 'black' >>> dict {'b': 'sky', 'c': 'earth'} >>> del dict['b'] >>> dict {'c': 'earth'} >>> dict.clear() >>> dict {}