The math.ceil() function in Python is used to return the smallest integer that is greater than or equal to a given number. This function is useful when you need to round a floating-point number up to the nearest whole number.

Syntax

import math
result = math.ceil(x)

• x: A numeric expression (integer or float) for which you want to find the ceiling value.

Return Value

• Returns the smallest integer greater than or equal to x, which is of type int.

Examples

1. Rounding up a positive float:

   import math
   
   result = math.ceil(4.2)
   print(result)  # Output: 5
   

2. Rounding up a negative float:

   result = math.ceil(-3.7)
   print(result)  # Output: -3
   

3. Rounding an integer: If you pass an integer to math.ceil(), it will return the integer itself.

   result = math.ceil(5)
   print(result)  # Output: 5
   

4. Rounding up a float that is already an integer:

   result = math.ceil(8.0)
   print(result)  # Output: 8
   

5. Using math.ceil() with complex expressions: You can use math.ceil() in expressions:

   a = 2.3
   b = 3.8
   result = math.ceil(a + b)
   print(result)  # Output: 6
   

6. Rounding very small decimal numbers:

   result = math.ceil(0.1)
   print(result)  # Output: 1
   

Summary

• The math.ceil() function returns the smallest integer greater than or equal to the input value.
• It works with both integers and floating-point numbers.
• The return type is always int.
• This function is particularly useful in scenarios where you need to ensure that a value is rounded up, such as calculating the number of pages needed for a certain number of items per page.