Question

What is the difference between an argument and a parameter variable?

Short answer

Answer: Arguments are the values passed to a function when it is called, while parameter variables are placeholders used in the function's definition to indicate the values the function is expecting. Arguments are provided by the caller of the function and can change from call to call, whereas parameter variables remain constant as placeholders within the function definition.

Step-by-step solution

Define an argument

An argument is a value that is passed into a function when the function is called. It serves as an input for the function, and its value will be used throughout the function. Arguments can be of different data types such as integers, strings, or objects, and the number of arguments depends on the specific function being called.

Define a parameter variable

A parameter variable is like a placeholder used in the function's definition to indicate that the function is expecting a value (or multiple values) when it is called. These variables are used within the function to represent the arguments that will be supplied when the function is called. Parameter variables can be of any data type and can have default values if needed.

Give an example for an argument and a parameter variable

Consider a simple Python function that adds two numbers: ```python def add_numbers(a, b): # a and b are parameter variables return a + b ``` When we call this function, we provide two values (arguments) that will be represented by the parameter variables 'a' and 'b' within the function: ```python result = add_numbers(3, 4) # 3 and 4 are the arguments being passed to the function print(result) # output: 7 ```

Compare and summarize the differences

In summary, arguments and parameter variables play complementary roles in functions: - Arguments are the values that are passed to a function when it is called. - Parameter variables are the placeholders used in the function's definition to indicate the values the function is expecting. It is important to remember that the parameter variables are used within the function and only represent the arguments passed when the function is called. The arguments themselves are provided by the caller of the function and can change from call to call, while parameter variables remain constant in their role as placeholders within the function definition.