Def custom_function(x, y, z=0):

General
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def custom_function(x, y, z=0):

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## What does the Python function definition def custom_function(x, y, z=0): mean?

Answer:
In Python, the syntax def custom_function(x, y, z=0): defines a function named custom_function with three parameters: x, y, and z. The parameter z has a default value of 0, meaning that if no argument is provided for z when calling the function, it will automatically be set to 0. Below is a detailed explanation of each part:

  1. Function Name:
    The word custom_function is the identifier you use to call the function.

  2. Parameters:

    • x: A required parameter.
    • y: Another required parameter.
    • z=0: A parameter with a default value. If you do not supply a value for z when calling the function, the default value 0 is used.

  3. Usage:

    • If you call custom_function(10, 20), then x=10, y=20, and z will default to 0.
    • If you call custom_function(10, 20, 5), then x=10, y=20, and z=5.

  4. Advantages of Default Parameters:

    • Flexibility: You can either specify a value for z or rely on the default if you don’t need to customize it.
    • Code Readability: Makes your function easier to read and maintain.

  5. Example:
    You might define the function to perform a simple sum of these parameters:

    def custom_function(x, y, z=0):
    return x + y + z
    • Calling custom_function(2, 3) returns 5.
    • Calling custom_function(2, 3, 1) returns 6.

Below is a summary in table form.

Parameter Type Default Value Description
x Number (int/float) None (Required) A required parameter, first positional argument.
y Number (int/float) None (Required) A required parameter, second positional argument.
z Number (int/float) 0 An optional parameter; defaults to 0 if no argument is provided.

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