How do you floor a number in Python?

How do you floor a number in Python?

To floor a number in Python, you can use the floor() function from the math module. The floor() function returns the largest integer less than or equal to a given number. Here's how you can use it:

import math

# Example usage
number = 3.7
floored_number = math.floor(number)
print(floored_number)  # Output: 3

In this example, math.floor(3.7) returns 3 because 3 is the largest integer less than or equal to 3.7.

What is the difference between floor and round functions in Python?

The floor() and round() functions in Python serve different purposes:

• floor(): This function returns the largest integer less than or equal to a given number. It always rounds down towards negative infinity. For example, math.floor(3.7) returns 3, and math.floor(-3.7) returns -4.
• round(): This function rounds a number to the nearest integer or to a specified number of decimal places. If the fractional part of the number is exactly halfway between two integers, Python's round() function uses the "round half to even" strategy (also known as "bankers' rounding"). For example, round(3.7) returns 4, round(3.2) returns 3, and round(2.5) returns 2 (not 3).

Here are some examples to illustrate the difference:

import math

print(math.floor(3.7))  # Output: 3
print(round(3.7))       # Output: 4

print(math.floor(-3.7)) # Output: -4
print(round(-3.7))      # Output: -4

print(math.floor(2.5))  # Output: 2
print(round(2.5))       # Output: 2

Can you use the floor function with negative numbers in Python?

Yes, you can use the floor() function with negative numbers in Python. When you apply floor() to a negative number, it returns the largest integer less than or equal to that number, which means it rounds down towards negative infinity. Here's an example:

import math

# Example usage with a negative number
number = -3.7
floored_number = math.floor(number)
print(floored_number)  # Output: -4

In this case, math.floor(-3.7) returns -4 because -4 is the largest integer less than or equal to -3.7.

How can you import the floor function from the math module in Python?

To import the floor() function from the math module in Python, you have a few options:

1. Import the entire math module:

import math

# Usage
number = 3.7
floored_number = math.floor(number)
print(floored_number)  # Output: 3

2. Import the floor function specifically:

from math import floor

# Usage
number = 3.7
floored_number = floor(number)
print(floored_number)  # Output: 3

3. Import the floor function with an alias:

from math import floor as fl

# Usage
number = 3.7
floored_number = fl(number)
print(floored_number)  # Output: 3

Each of these methods allows you to use the floor() function, but the syntax for calling it may vary depending on how you import it.

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