DAX - Nested Calculated queries - nested

Question

I have a large data file (4.2mil rows and 10 columns) and I'm trying to do some filtering with measures. However, when I try to use nested measures everything explodes and I'm not really sure why.
So far, I have two explicit measures:
MaxValue:=MAX('Element Forces - Area Shells'[Value])
and
MaxIndex:=
CALCULATE(
FIRSTNONBLANK('Element Forces - Area Shells'[Index],1),
FILTER(
ALL('Element Forces - Area Shells' ),
'Element Forces - Area Shells'[Value]=MAX('Element Forces - Area Shells'[Value])
)
)
This works and I get a correct values. However, as I see it, I should be able to put the MaxValue measure into the MaxIndex measure, but then everything just stops.
The new measure I'm picturing should look like this:
MaxIndex:=
CALCULATE(
FIRSTNONBLANK('Element Forces - Area Shells'[Index],1),
FILTER(
ALL('Element Forces - Area Shells' ),
'Element Forces - Area Shells'[Value]=[MaxValue])
)
)
But it just doesn't work. What am I doing wrong?

Answer 1

Although I can't test it right now, I think it's caused by the implicit context transition*. When you're referencing a measure in another measure, internally a CALCULATE() is involved and therefor a context transition. That's not wat you want in this case. I advise you to use a variable, in order to create one measure:
MaxIndex:=
VAR MaxValue = MAX('Element Forces - Area Shells'[Value])
RETURN
CALCULATE(
FIRSTNONBLANK('Element Forces - Area Shells'[Index],1),
FILTER(
ALL('Element Forces - Area Shells' ),
'Element Forces - Area Shells'[Value] = MaxValue )
)
)
Note: I'm not sure, please forgive me if I'm wrong :)
In addition, the use of VAR, from the MSDN docs:
This feature is included in SQL Server 2016 Analysis Services (SSAS), Power Pivot in Excel 2016, and Power BI Desktop only. Information provided here is subject to change.