Python intensive dictionary introduction

Constructors

d = {}                             # dict literal notation
d = dict()

d = {'one': 1, 'two': 2}           # dict literal
d = dict([('one', 1), ('two', 2)]) # list of tuples
d = dict(one=1, two=2)             # keyword arguments
Dictionary from key value pair
>>> keys = "one two three".split()
>>> values = "1 2 3".split()
>>> keys
['one', 'two', 'three']
>>> values
['1', '2', '3']
>>> d = dict(zip(keys, values))
>>> d
{'three': '3', 'two': '2', 'one': '1'}
Set default Values
d = dict(zip(keys, [0] * len(keys)))

That's because zip generates tuple. Tuple can convert to list. * means do the same thing as the number.


This is the same to above.

keys = ['one', 'two', 'three']
value = 0
d = dict.fromkeys(keys, value)     # builds a dictionary single list of keys