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richard-powerbi
Post Patron
Post Patron

Opposite of sum function

So there's the SUM function as a measure or explicit measure.

 

A, 10

A, 20

B, 15

 

Returns this:

 

A, 30

B, 15

 

Now let's say a faulty table already summed the values, but the amount of rows is equal to the amount of rows before the sum. Like this:

 

A, 30

A, 30

B, 15

 

How can I create the opposite measure of SUM that divides the value by the count it occurs per group (A/B in this example), resulting in this:

 

A, 15

A, 15

B, 15

 

As you can see the end result is more like a prediction than true to reality, but that's okay.

Thanks!

5 REPLIES 5
harshnathani
Community Champion
Community Champion

Hi @richard-powerbi ,

 

Count the number of rows for each id and divide it by the total.

 

 

Create a Calculated Column

 

Rows_id =
var a = CALCULATE(COUNT('Table'[Column1]),ALLEXCEPT('Table','Table'[Column1]))
RETURN
DIVIDE('Table'[Column2],a)

 

Regards,

Harsh Nathani

mahoneypat
Microsoft Employee
Microsoft Employee

Here is an expressiont that works with your sample data.  I called the table 'Reverse'.

 

Reverse Sum =
VAR __thisletter =
    MIN ( Reverse[Letter] )
VAR __count =
    CALCULATE (
        COUNTROWS ( Reverse ),
        ALL ( Reverse ),
        Reverse[Letter] = __thisletter
    )
VAR __thisaverage =
    AVERAGE ( Reverse[Number] )
RETURN
    DIVIDE ( __thisaverage, __count )

 

If this works for you, please mark it as the solution.  Kudos are appreciated too.  Please let me know if not.

Regards,

Pat





Did I answer your question? Mark my post as a solution! Kudos are also appreciated!

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lbendlin
Super User
Super User

Don't use DAX to fix a mistake that was made in a previous step. Prevent that mistake in your process.

@lbendlin I wouldn't be asking this if I could fix it in a previous proces...

 

@stevedep thanks but I don't see how this could help me...

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