test is any value or expression that can be TRUE or FALSE.
then value (optional) is the value that is returned if the logical test is TRUE.
otherwise value (optional) is the value that is returned if the logical test is FALSE.
In IBM Docs functions, parameters marked as optional can be left out only when no parameter follows. For example, in a function with four parameters, where the last two parameters are optional, you can leave out parameter 4 or parameters 3 and 4. However, you cannot leave out parameter 3 alone.
If the value in A1 is higher than 5, the value 100 is entered in the current cell; otherwise, the text "too small" (without quotes) is entered.
Parent topic: Logical functions