Positional Arguments and Keyword Arguments in Python [ English ]

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1. Introduction

When calling a function in Python, arguments can be supplied in different ways. The two most common and fundamental methods are:

• Positional Arguments (based on order)
• Keyword Arguments (based on parameter names)

Understanding these forms is essential for writing correct and readable function calls.

2. Positional Arguments

2.1 Definition

Positional arguments are passed to a function in the same order as the parameters are defined. Each value is assigned to a parameter according to its position.

2.2 Example

def display(name, age):
    print("Name:", name)
    print("Age:", age)

display("Rahul", 20)

Output:

Name: Rahul
Age: 20

Here:

• "Rahul" → assigned to name
• 20 → assigned to age

2.3 Important Rule

The order must be correct.

display(20, "Rahul")

Output:

Name: 20
Age: Rahul

This produces incorrect results because the arguments are swapped.

3. Keyword Arguments

3.1 Definition

Keyword arguments are passed by explicitly specifying the parameter name and its value. This removes the dependency on position.

3.2 Example

def display(name, age):
    print("Name:", name)
    print("Age:", age)

display(age=20, name="Rahul")

Output:

Name: Rahul
Age: 20

3.3 Advantages

• Order does not matter
• Improves readability
• Reduces logical errors

4. Combining Positional and Keyword Arguments

You can use both in the same function call.

def student(name, age, city):
    print(name, age, city)

student("Rahul", age=20, city="Jaipur")

✔ Valid usage

4.1 Rule to Follow

Positional arguments must always come before keyword arguments.

✘ Invalid:

student(name="Rahul", 20, city="Jaipur")

This results in a syntax error.

5. Comparison

6. When to Use

• Use positional arguments when:

  • The function is simple
  • The parameter order is obvious

• Use keyword arguments when:

  • The function has many parameters
  • Clarity and readability are important
  • Default values are involved

7. Key Insight

Positional arguments are concise but can lead to errors if the order is incorrect. Keyword arguments enhance clarity and make code self-explanatory, especially in complex functions.

8. Conclusion

Both positional and keyword arguments are essential tools in Python. A good programmer knows when to use each appropriately to write clean, efficient, and maintainable code.