What is Floor Division?
In Python, floor division is a mathematical operation that returns the largest integer that is less than or equal to the division of two numbers. It is denoted by the double forward slash operator (//). Unlike regular division, which returns a floating-point number, floor division always returns an integer.
Using the Floor Division Operator
To perform floor division in Python, you can use the double forward slash operator (//). The syntax is as follows:
result = dividend // divisor
The dividend is the number that you want to divide, and the divisor is the number that you want to divide by. The result is the largest integer that is less than or equal to the division of the dividend by the divisor.
Examples of Floor Division
Let’s look at some examples to understand how floor division works in Python.
Example 1:
result = 10 // 3
print(result)
Output: 3
In this example, the division of 10 by 3 is 3.3333. However, since we are using floor division, the result is rounded down to the nearest integer, which is 3.
Example 2:
result = 15 // 4
print(result)
Output: 3
In this example, the division of 15 by 4 is 3.75. Again, since we are using floor division, the result is rounded down to the nearest integer, which is 3.
Example 3:
result = 20 // 5
print(result)
Output: 4
In this example, the division of 20 by 5 is 4. However, since 4 is already an integer, the result remains the same.
Handling Negative Numbers
When dealing with negative numbers, floor division in Python follows the rule of rounding towards negative infinity. This means that the result is always rounded down to the nearest integer that is less than or equal to the division of the dividend by the divisor.
Example 4:
result = -10 // 3
print(result)
Output: -4
In this example, the division of -10 by 3 is -3.3333. Since we are rounding towards negative infinity, the result is rounded down to the nearest integer, which is -4.
Example 5:
result = -15 // 4
print(result)
Output: -4
In this example, the division of -15 by 4 is -3.75. Again, since we are rounding towards negative infinity, the result is rounded down to the nearest integer, which is -4.
Using Floor Division with Variables
You can also use variables in floor division operations in Python. Here’s an example:
Example 6:
dividend = 25
divisor = 7
result = dividend // divisor
print(result)
Output: 3
In this example, we assign the value 25 to the variable dividend and the value 7 to the variable divisor. We then perform floor division using these variables and store the result in the variable result. The result is 3, which is the largest integer that is less than or equal to the division of 25 by 7.
Conclusion
Floor division in Python is a useful mathematical operation that allows you to divide two numbers and obtain the largest integer that is less than or equal to the division. It is denoted by the double forward slash operator (//) and always returns an integer. When dealing with negative numbers, floor division follows the rule of rounding towards negative infinity. You can use floor division with both literal values and variables in Python.