| # Python code to demonstrate how it works
# fromkeys () and update ()
# Initializing dictionary 1 dic1 = { ’ Name’ : ’Nandini’ , ’Age’ : 19 }
# Initializing Dictionary 2 dic2 = { ’ID’ : 2541997 }
# Initializing sequence sequ = ( ’ Name’ , ’Age’ , ’ID’ )
# using update to add dic2 values to dic 1
dic1.update (dic2)
# print updated dictionary values print ( "The updated dictionary is:" ) print ( str (dic1))
# using fromkeys () to convert sequence to dictionary dict = dict . fromkeys (sequ, 5 )
# print new dictionary values print ( "The new dictionary values are:" ) print ( str ( dict )) |
Output:
The updated dictionary is: {’Age’: 19 , ’Name’:’ Nandini’, ’ID’: 2541997} The new dictionary values are: {’ Age’: 5, ’Name’: 5,’ ID’: 5}
3. has_key () : — This function returns true if the specified dictionary is in the dictionary, otherwise it returns false.
4. get (key, def_val) : — This function returns the key value associated with the key mentioned in the arguments. If the key is missing, the default is returned.
| # Python code to demonstrate how it works
# has_key () and get ()
# Dictionary initialization dict = { ’Name’ : ’ Nandini’ , ’Age’ : 19 }
# using has_key () to check if there is dic1 has a key if dict . has_key ( ’Name’ ): print ( "Name is a key" ) else : print ( "Name is not a key" )
# using get () to print the key value print ( "The value associated with ID is:" ) print ( dict . get ( ’ID’ , "Not Present" ))
# print dictionary values print ( "The dictionary values are:" ) print ( str ( dict )) |
Output:
Name is a key The value associated with ID is: Not Present The dictionary values are: {’Name’:’ Nandini’, ’Age’: 19}
5. setdefault (key, def_value) : — This function also looks for a key and displays its value like get (), but creates a new key with def_value if the key is missing.
| # Python code to demonstrate how it works
# set as default ()
# Initializing the dictionary dict = { ’Name’ : ’Nandini’ , ’ Age’ : 19 }
# using setdefault () to print the key value print ( "The value associated with Age is:" , end = "") print ( dict . setdefault ( ’ID’ , " No ID " ))
# print dictionary values print ( "The dictionary values are:" ) print ( str ( dict )) |
Output:
The value associated with Age is: No ID The dictionary values are: {’Name’:’ Nandini’, ’Age’: 19,’ ID’ : ’No ID’}
This article is courtesy of Manjeet Singh . If you are as Python.Engineering and would like to contribute, you can also write an article using contribute.python.engineering or by posting an article contribute @ python.engineering. See my article appearing on the Python.Engineering homepage and help other geeks.
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