Question

The following statements call a function named . Which of the statements passes arguments by position, and which passes keyword arguments? a. show data (name=' Kathryn', age=25) b. show data ('Kathryn', 25)

Short answer

a. show_data(name='Kathryn', age=25) b. show_data('Kathryn', 25) Answer: Function call (a) passes keyword arguments, and function call (b) passes arguments by position.

Step-by-step solution

Identify the format of arguments in each function call

In both function calls, let's pay attention to the way that arguments are passed: a. show_data(name='Kathryn', age=25) b. show_data('Kathryn', 25) In the first function call, we have arguments with an explicit parameter name followed by an equal sign and the value. In the second function call, we have values without any explicit parameter names.

Determine the type of argument passing in each function call

Now, based on the format of arguments in both function calls, we can classify them into positional or keyword arguments. a. show_data(name='Kathryn', age=25): In this function call, the arguments are explicitly assigned to parameter names, making the order irrelevant. Hence, this function call passes keyword arguments. b. show_data('Kathryn', 25): In this function call, the arguments are provided in the same order without specifying parameter names. Hence, this function call passes arguments by position.

Key concepts

Positional Arguments

Positional arguments are a fundamental aspect of function calls in Python. These arguments are passed to a function in a specific order that corresponds to the order in which the parameters are defined in the function declaration. This order is crucial because the arguments are mapped to parameters based solely on their position.

For example, if we define a function show_data(name, age) and we call it as show_data('Kathryn', 25), 'Kathryn' is assigned to the parameter name and 25 to age because of their respective positions. When using positional arguments, it is important to provide all required arguments, and any mismatch in the number of arguments or their order can result in errors or unintended behavior.

Keyword Arguments

In contrast to positional arguments, keyword arguments allow you to pass values to specific parameters regardless of their order in the function's signature. By using the names of parameters in a function call, you can specify which argument corresponds to which parameter. This is particularly useful for functions that take many parameters or when you want to only provide values for certain parameters, leaving the rest to their default values if defined.

Take the function call show_data(name='Kathryn', age=25) as an example. Here, 'Kathryn' is associated with the parameter name and 25 with age, but this time, their order doesn't affect the assignment. Keyword arguments increase the readability of code and reduce the likelihood of passing arguments in the wrong order, making them a desirable feature for complex functions.

Function Calls in Python

A function call in Python is the process of executing a predefined function by passing the required data, known as arguments, into it. This action activates the function's code block and returns a result if the function is designed to do so. There are several ways to call a function in Python, using positional arguments, keyword arguments, or a combination of both.

To appropriately call a function, you need to understand the defined parameters of the function, as incorrect function calls can lead to errors. For instance, calling show_data('Kathryn', age=25) uses both positional and keyword arguments. This flexibility in function calls highlights Python's adaptability and underscores the importance of understanding the different types of arguments.

Parameters in Python

Parameters are variables that are used in a function's definition to receive values when the function is called. They form the interface through which a function can accept inputs from the outside, making the function reusable with different data. In Python, parameters come in different types such as required (positional) parameters, optional parameters (which have default values), and arbitrary parameters (which allow passing a variable number of arguments).

Understanding parameters is crucial for defining functions that are flexible and maintainable. For example, defining a function with def show_data(name, age=18), makes name a required parameter and age an optional parameter with a default value. When we call this function with only one argument, like show_data('Alex'), the function still runs smoothly since age defaults to 18.