DAX NOT Function

The DAX NOT function in Power BI is used to reverse the logical value of an expression. It returns TRUE if the input expression evaluates to FALSE, and FALSE if the input expression evaluates to TRUE. This function is useful for creating conditions where you need the opposite of a given logical expression.

Syntax:

NOT(<logical>)

<logical>: The condition or expression to be negated.

Purpose:

The NOT function allows you to negate a logical condition. This can be essential when you want to create conditions that exclude specific criteria or reverse the outcome of a logical test.

Example:

Suppose you have a table named "Sales" with columns "Product", "Revenue", and "UnitsSold". You want to create a new column that flags sales as "Not High Revenue" if the revenue is not greater than 200.

You can use the NOT function as follows:

NotHighRevenue = IF(NOT(Sales[Revenue] > 200), "Yes", "No")

This formula creates a new column named "NotHighRevenue" that assigns "Yes" if the revenue is not greater than 200, and "No" otherwise.

Example Scenario:

Consider the following "Sales" table with columns "Product", "SalesAmount", and "Cost".

We want to create a new calculated column called "HighCost" that indicates whether the cost is not less than 100 (i.e., the cost is 100 or more).

HighCost = NOT(Sales[Cost] < 100)

The resulting table would be:

Combining NOT with IF Function

For a more meaningful result, we can combine the NOT function with the IF function:

HighCost = IF(NOT(Sales[Cost] < 100), "High Cost", "Low Cost")

In this example, rows where the cost is 100 or more are labeled "High Cost", and rows where the cost is less than 100 are labeled "Low Cost". This demonstrates how the NOT function can be used to reverse the logical condition in a DAX formula.