# Python program to demonstrate working
# of map.
# Return double of n
def addition(n):
return n + n
# We double all numbers using map()
numbers = (1, 2, 3, 4)
result = map(addition, numbers)
print(list(result))
# Output :-
# 1 + 1 = 2 / 2 + 2 = 4 / 3 + 3 = 6 / 4 + 4 = 8
[2, 4, 6, 8]
# Example With Strings :-
# List of strings
my_list = ['sat', 'bat', 'cat', 'mat']
# map() can listify the list of strings individually
test = list(map(list, my_list))
print(test)
# Output :-
# listify the list of strings individually Like :-
# 'sat' 3 Letters ==> The Function is Offered Individually :- 's', 'a', 't'
[['s', 'a', 't'], ['b', 'a', 't'], ['c', 'a', 't'], ['m', 'a', 't']]
# The map function applies a function to every item in a list,
# and returns a new list.
numbers = [0, -1, 2, 3, -4]
def square_func(n):
return n*n
new_numbers = list(map(square_func, numbers))
#new_numbers: [0, 1, 4, 9, 16]
# Python program to demonstrate working
# of map.
# Return double of n
def addition(n):
return n + n
# We double all numbers using map()
numbers = (1, 2, 3, 4)
result = map(addition, numbers)
print(list(result))
# Program to double each item in a list using map()
my_list = [1, 5, 4, 6, 8, 11, 3, 12]
new_list = list(map(lambda x: x * 2 , my_list))
print(new_list)
# Let's define general python function
>>> def doubleOrNothing(num):
... return num * 2
# now use Map on it.
>>> map(doubleOrNothing, [1,2,3,4,5])
<map object at 0x7ff5b2bc7d00>
# apply built-in list method on Map Object
>>> list(map(doubleOrNothing, [1,2,3,4,5])
[2, 4, 6, 8, 10]
# using lambda function
>>> list(map(lambda x: x*2, [1,2,3,4,5]))
[2, 4, 6, 8, 10]
# Python program to demonstrate working
# of map.
# Return double of n
def addition(n):
return n + n
# We double all numbers using map()
numbers = (1, 2, 3, 4)
result = map(addition, numbers)
print(list(result))
# result [2, 4, 6, 8]
# Python program to demonstrate working
# of map.
# Return double of n
def addition(n):
return n + n
# We double all numbers using map()
numbers = (1, 2, 3, 4)
result = map(addition, numbers)
print(list(result))
'''
Map:
A standard function that accepts at least "two-arguments",
a function and an "iterable"
Iterable - something that can be iterated over (list, dictionary,
strings, sets, tuples)
runs the Lambda for each value in the iterable and
returns a map object which can be converted into another data structure
Keyword:
map(function/lambda func., variable)
'''
# Example:
nums = [1,2,3,4]
power = map(math.pow(2), nums)
print(list(power)) # 1, 4, 9, 16
powerLamb = map(lambda x: x**2, nums) # 1, 4, 9, 16
map() is a higher-order built-in function that takes a function and iterable as inputs,
and returns an iterator that applies the function to each element of the iterable.
// if you want to take single int input
a=int(input())
// if you want n elements of array a as input from console/user
a = list(map(int,input().strip().split()))
# u can also covert it to set,tuple etc
# ex. set(map(int, input().strip().split()))
NOTE: suppose if you want a list with duplicates removed
list(set(map(int, input().strip().split())))
also note map is a method and is not hashmap which is actually disct in python.
and ommitting .strip() in 2nd argument of map func might also work.
# more explaination of above:
https://www.quora.com/What-does-the-following-line-mean-in-Python-list-map-int-input-strip-split-I
# Python program to demonstrate working
# of map.
# Return double of n
def addition(n):
return n + n
# We double all numbers using map()
numbers = (1, 2, 3, 4)
result = addition(numbers)
print(list(result))
price_list=[120,250,133,420,145,369,700]
# given alist of prices
def sale(price):
# function for add discount in sale for evry price
discount=(15/100)
# discount 15%
new_price = price*discount
# new price
return new_price
new_price_list=list(map(sale,price_list))
# 120*15% , 250*15)3*15%
# use map function take evry price in price list
# add evry price to slae funtion
# add discount to this price return new price
# add evry new price in new_price_list
print(f"price list in sale {new_price_list}")
#print new list of prices
#The map function is used to do a certain function to a certain iterable
#It takes a function and an iterable
numbers = [1,2,3,4,5,6,7,8,9,10]
x = map(lambda nom : nom*nom, numbers)
print(list(x))
#So here my function is the lambda and the iterable is the numbers list
#And with this I apply nom*nom to every item to the list
# if I didn't put the list function before x it would print map object at .....