Dictionary?
In python, dictionary is similar to hash or maps in other languages. It consists of key value pairs. The value can be accessed by unique key in the dictionary.
Create a new dictionary
Create a new dictionary
d = dict()
# or you can do
d = {}
Add a key - value pairs to dictionary
Add a key - value pairs to dictionary
d[‘xyz’] = 123
d[‘abc’] = 345
returns {‘xyz’: 123, ‘abc’: 345}
print the whole dictionary
print the whole dictionary
print(d)
print only the keys
A
# print only the keys
print(d.keys())
returns [‘key1’, ‘key2’,…]
#notice the parens around the keys
print only values
print only values
print(d.values())
returns [value1, value2]
#notice the lack of parens around the values
iterate over dictionary
iterate over dictionary
for i in d :
print(“%s %d” %( i, d[i] ) )
another way of iteration over a dictionary
another method of iteration
for index, value in enumerate(d):
print (index, value , d[value])
check if key exist
check if key exist
print(‘xyz’ in d)
delete the key-value pair
delete the key-value pair
del d[‘xyz’]
Dict.cmp()
Dict.cmp(): Compares elements of both dict.
Dict.len()
Dict.len(): Gives the total length of the dictionary.
Dict.str()
Dict.str(): Produces a printable string representation of a dictionary.
Dict.type()
Dict.type(): Returns the type of the passed variable
Dict.clear()
Dict.clear(): Removes all elements of dictionary dict
Dict.copy()
Dict.copy(): Returns a shallow copy of dictionary dict
