Python lambda if-else function is used to choose a return value based on some condition.
Syntax: if-else in lambda function is a little tricky
lambda <arguments> : <Return Value if condition is True> if <condition> else <Return Value if condition is False>Simple
lambda <arguments> : <value_1> if <condition> else <value_2>Using if else in Lambda function Python
Simple example code Lambda Function with If Else Condition.
Example 1
if the given value is between 10 and 20 then it will return True else it will return False.
foo = lambda x: True if (10 < x < 20) else False
print(foo(12))
print(foo(3))
Output:
Example 2
A lambda function that returns the square of the number if the number is even, else cube of the number.
x = lambda n: n ** 2 if n % 2 == 0 else n ** 3
print(x(4))
print(x(3))
Output:
16
27
Example 3
Using filter() function with a conditional lambda function with if-else. Filter numbers between 10 to 20 only.
Num = [1, 3, 33, 12, 34, 56, 11, 19, 21, 34, 15]
res = list(filter(lambda x: 10 < x < 20, Num))
print('Filtered List : ', res)
Output: Filtered List : [12, 11, 19, 15]
Keep in mind that while lambda functions are useful for short, one-line expressions, for more complex logic, it’s often better to use a regular named function. Lambda functions are limited to a single expression and can’t include statements or multiple expressions.
Do comment if you have any doubts or suggestions on this Python lambda topic.
Note: IDE: PyCharm 2021.3.3 (Community Edition)
Windows 10
Python 3.10.1
All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.