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)
