What is a lambda function in Python?

What is a lambda function in Python?

• A. A standard function defined with def
• B. An anonymous function defined with the lambda keyword
• C. A function that takes no parameters
• D. A function that always returns None

Answer: (B)

A lambda function in Python is defined using the lambda keyword and is characterized as an anonymous function. This means that it does not require a name to be defined, which distinguishes it from standard functions that are created using the def keyword. Lambda functions are typically used for creating small, single-use functions in a concise way, allowing for quick definitions that can be useful in situations where a full function might be overkill. They can take any number of arguments but can only have a single expression, which is evaluated and returned when the function is called. This feature makes lambda functions particularly useful in functional programming constructs, such as when using higher-order functions like map(), filter(), and reduce(), where they help to keep the code clean and focused on the task at hand without needing to formally define a separate function. Understanding lambda functions is essential as they allow for more flexible and efficient coding practices in Python.

A lambda function in Python is defined using the lambda keyword and is characterized as an anonymous function. This means that it does not require a name to be defined, which distinguishes it from standard functions that are created using the def keyword.

Lambda functions are typically used for creating small, single-use functions in a concise way, allowing for quick definitions that can be useful in situations where a full function might be overkill. They can take any number of arguments but can only have a single expression, which is evaluated and returned when the function is called.

This feature makes lambda functions particularly useful in functional programming constructs, such as when using higher-order functions like map(), filter(), and reduce(), where they help to keep the code clean and focused on the task at hand without needing to formally define a separate function.

Understanding lambda functions is essential as they allow for more flexible and efficient coding practices in Python.