Which function is used to calculate the smallest integer greater than or equal to a number?

The function used to calculate the smallest integer greater than or equal to a number is called "ceil" function. Here is how you can use it:

1. First, you need to import the math module in your program. You can do this by writing "import math" at the beginning of your code.

2. Once you have imported the math module, you can use the "math.ceil()" function. Inside the parentheses, you put the number you want to find the smallest integer greater than or equal to.

3. The function will then return the smallest integer that is greater than or equal to the number you put in.

For example, if you want to find the smallest integer greater than or equal to 2.3, you would write "math.ceil(2.3)". The function would return 3, because 3 is the smallest integer that is greater than 2.3.