How to get the SUM of TOPN values where some values have an equal value?

[rflook]

Hi, after some kind soul on here helped me out with a TOPN issue, I have another issue that I'm hoping someone can help me with. I'm trying to sum together the top 8 achievement grades for a selected pupil. Currently I'm using the following

Best8List = var _top =
   TOPN(8,
        FILTER(

           'Report-Ach',

           'Report-Ach'[intGradeTransposeValue]>=5 && 'Report Ach'[intReportCycleID] = 'PupilData'[LastRepCycleID] && 'Report-Ach'[txtSchoolID] = 'PupilData'[txtSchoolID]),

       'Report-Ach'[intGradeTransposeValue],
        DESC)
return
   SUMX(_top,'Report-Ach'[intGradeTransposeValue])

The issue I am facing is that if a student has several grades that are the same, it includes those values in the sum. So for example if t a student's grade set was: 9, 9, 9, 9, 8, 8, 8, 8, 8, 8, 8, all of the 8s and all of the 9s will be included in the sum. What I actually want is for the 9s to be included, and four of the 8s. 

I thought perhaps I need to use RANKX alongwith TOPN but I'm not really sure how to do this. Can any kind soul help?

[parry2k]

@rflook in your measure you are using some other columns and that's what I'm trying to get to. You can just list the columns and how you want to visualize it (or calculating rank)

[rflook]

Here is some sample data:

txtSchoolID	intReportCycleID	intGradeTransposeValue
851753944746	328	9
851753944746	328	8
851753944746	328	9
851753944746	328	9
851753944746	328	9
851753944746	328	8
851753944746	328	9
851753944746	328	9
851753944746	328	8
851753944746	328	8

So for this student, if we were to rank his scores, it would be 9,9,9,9,9,9,8,8,8,8. I want to sum the top 8 of these scores, so 9+9+9+9+9+9+8+8 = 70

[parry2k]

@rflook also in this case I will use the new ROWNUMBER function and that will make it super easy.

[parry2k]

@rflook can you share sample data, also is this a column or a measure? 'Report-Ach'[intGradeTransposeValue] or

[rflook]

It's a calculated column. I could show some data if you really need it, but not until tomorrow as I can only access the data set from my work IP address. 

[parry2k]

@rflook why four of 8's what is the logic?

[rflook]

Well, I need the top 8 values from the student's results, so that would be four 9s and then four 8s. I just realised my TOPN was wrong in the code snippet I posted (that was after I tried to figure out what was going wrong). I have just editted it for the top 8 results.