lambda function in python
In Python, an anonymous function is a function that is defined without a name.
While normal functions are defined using the def keyword in Python,
anonymous functions are defined using the lambda keyword.
Hence, anonymous functions are also called lambda functions.
# syntax of Lambda function
lambda arguments: expression
# Program to show the use of lambda functions
double = lambda x: x * 2
print(double(5))
# examples
my_list = range(101)
print(list(map(lambda item: item**2, my_list)))
print(list(filter(lambda item: item % 2 == 1, my_list)))
print(list(map(lambda item: item**2, my_list)))
a = [(0, 2), (4, 3), (9, 9), (10, -1)]
a.sort(key=lambda x: x[1])
print(a)
# docs lambda function
# the lambda function can be used as a function inside a function like the following
def make_incrementor(n):
return lambda x: x + n
f = make_incrementor(12)
print(f(3))
print(f(13))
# you can use lambda as a key for sort or anything else
pairs = [(1, "one"), (2, "two"), (3, "three"), (4, "four")]
# what if you wanna sort the list by the second argument
pairs.sort(key=lambda x: x[1])
print(pairs)