How To Calculate % In Python

Calculating percentages is a common task in programming, and Python makes it simple to perform these calculations. In this tutorial, we will learn how to calculate percentages in Python using various methods, including using the percentage symbol %, performing calculations in single lines of code, and creating a function.

Step 1: The basics of calculating percentages

To calculate a percentage, we typically follow this formula:

Percentage = (part / whole) * 100

For example, if we want to calculate the percentage of a number, we can divide the part (the portion we want to find out) by the whole (the total amount) and then multiply the result by 100.

In Python, this calculation can be written as follows:

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part = 25
whole = 200
percentage = (part / whole) * 100

In this example, we are calculating the percentage of 25 out of a whole of 200.

Step 2: Calculating percentages in a single line of code

We can also calculate percentages in a single line of code, making our code shorter and easier to read:

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percentage = (25 / 200) * 100

This one-line solution has the same effect as the previous method but streamlines the process.

Step 3: Using a function to calculate percentages

If you need to calculate percentages frequently, you can create a function to do the job faster. Here’s an example of a function that calculates percentages:

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def calculate_percentage(part, whole):
    return (part / whole) * 100

Now, you can easily calculate percentages by calling the calculate_percentage() function and providing the values for part and whole:

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percentage = calculate_percentage(25, 200)

Step 4: Calculating percentages using the Modulo Operator (%)

Python has a built-in operator called the “modulo operator” (%), which calculates the remainder after division. Though it’s not used for calculating percentages directly, it can be helpful in scenarios where you need to determine whether a number is a multiple of a certain percentage.

For example, let’s say we want to find out if a number is divisible by 7:

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number = 35
divisible_by_seven = number % 7 == 0

If divisible_by_seven is True, the number is divisible by 7 (meaning 7 is a factor of the number).

Full code:

Here is the full code for the various methods of calculating percentages discussed in this tutorial:

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def calculate_percentage(part, whole):
    return (part / whole) * 100
 
part = 25
whole = 200
percentage_basic = (part / whole) * 100
percentage_single_line = (25 / 200) * 100
percentage_function = calculate_percentage(25, 200)
 
number = 35
divisible_by_seven = number % 7 == 0
 
print("percentage_basic:", percentage_basic)
print("percentage_single_line:", percentage_single_line)
print("percentage_function:", percentage_function)
print("divisible_by_seven:", divisible_by_seven)

Output:

percentage_basic: 12.5
percentage_single_line: 12.5
percentage_function: 12.5
divisible_by_seven: True

Conclusion

In this tutorial, we have learned how to calculate percentages in Python using different methods, including using the basic formula for percentages, performing calculations in a single line of code, and creating a function for calculating percentages.

We also discussed how the modulo operator (%) can be used in situations where we need to determine if a number is a multiple of a certain percentage. With these techniques, you can easily calculate and work with percentages in your Python projects.