Python map() function
map() function returns a map object(which is an iterator) of the results after applying the given function to each item of a given iterable (list, tuple etc.)
Syntax :
map(fun, iter)
Parameters :
fun : It is a function to which map passes each element of given iterable.
iter : It is a iterable which is to be mapped.
NOTE : You can pass one or more iterable to the map() function.
Returns :
Returns a list of the results after applying the given function to each item of a given iterable (list, tuple etc.)
NOTE : The returned value from map() (map object) then can be passed to functions like list() (to create a list), set() (to create a set) .
CODE 1
# Python program to demonstrate working# of map. # Return double of ndef addition(n): return n + n # We double all numbers using map()numbers = (1, 2, 3, 4)result = map(addition, numbers)print(list(result)) |
Output :
[2, 4, 6, 8]
CODE 2
We can also use lambda expressions with map to achieve above result.
# Double all numbers using map and lambda numbers = (1, 2, 3, 4)result = map(lambda x: x + x, numbers)print(list(result)) |
Output :
[2, 4, 6, 8]
CODE 3
# Add two lists using map and lambda numbers1 = [1, 2, 3]numbers2 = [4, 5, 6] result = map(lambda x, y: x + y, numbers1, numbers2)print(list(result)) |
Output :
[5, 7, 9]
CODE 4
# List of stringsl = ['sat', 'bat', 'cat', 'mat'] # map() can listify the list of strings individuallytest = list(map(list, l))print(test) |
Output :
[['s', 'a', 't'], ['b', 'a', 't'], ['c', 'a', 't'], ['m', 'a', 't']]
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