Dynamically select column based on slicer for regression/correlation calculation

Hi Anonymous 
Here I'm using Field Parameters for dynamic selection of the X-Axis and Y-Axis. However, when trying to calculate the slope and intersection dynamically I hit the wall :-DI have a strong feeling that there should be a much simpler way to accomplish the same but this is what I was able to accomplish so far.
Worth mentioning that with hundreds of columns and thousands of rows this solution might not be feasible in terms of performance.
Also note that I don't have very strong visualization skills and I didn't know how how to add the manual trend line to the scattered plot so I just overlapped it with a line chart. Please do not laugh at that 🙂

Greg_Deckler Appreciate your input on this. Was that over thinking or it is just what it is?

Regression Value = 
VAR XColumn = MAX ( 'X-Axis'[Parameter] )
VAR YColumn = MAX ( 'Y_Axis'[Parameter] )
VAR T = ALLSELECTED ( 'Table' )
VAR NumberOfRows = COUNTROWS ( T )
VAR String1 = TOCSV ( T, -1, ",", TRUE )
VAR Items1 = SUBSTITUTE ( String1, UNICHAR ( 10 ), "|" )
VAR T1 = GENERATESERIES ( 1, NumberOfRows, 1 )
VAR T2 = SELECTCOLUMNS ( T1, "@Headers", PATHITEM ( Items1, 1 ), "@Details", PATHITEM ( Items1, [Value] + 1 ) )
VAR T3 =
    GENERATE ( 
        T2, 
        VAR HeaderString = [@Headers]
        VAR HeaderItems = SUBSTITUTE ( HeaderString, ",", "|" )
        VAR DetailString = [@Details]
        VAR DetailItems = SUBSTITUTE ( DetailString, ",", "|" )
        VAR Length = PATHLENGTH ( HeaderItems )
        VAR T4 = GENERATESERIES ( 1, Length, 1 )
        VAR T5 = SELECTCOLUMNS ( T4, "@Header1", PATHITEM ( HeaderItems, [Value] ), "@Detail1", PATHITEM ( DetailItems, [Value] ) )
        VAR T6 = SELECTCOLUMNS ( T4, "@Header2", PATHITEM ( HeaderItems, [Value] ), "@Detail2", PATHITEM ( DetailItems, [Value] ) )
        VAR T7 = FILTER ( T5, [@Header1] = "'Table'[" & XColumn & "]"  )
        VAR T8 = FILTER ( T6, [@Header2] = "'Table'[" & YColumn & "]"  )
        RETURN
            CROSSJOIN ( T7, T8 )
    )
VAR LinestTable = LINESTX ( T3, [@Detail2], [@Detail1] )
VAR Slope = MAXX ( LinestTable, [Slope1] )
VAR Intercept = MAXX ( LinestTable, [Intercept] )
VAR X = 
    MAXX (
        'Table',
        VAR T1 = CALCULATETABLE ( 'Table' )
        VAR String1 = TOCSV ( T1, 1, ",", TRUE )
        VAR Items1 = SUBSTITUTE ( String1, UNICHAR ( 10 ), "|" )
        VAR T2 = SELECTCOLUMNS ( { ( 1, 2 ) }, "@Headers", PATHITEM ( Items1, 1 ), "@Details", PATHITEM ( Items1, 2 ) )
        VAR T3 =
            GENERATE ( 
                T2, 
                VAR HeaderString = [@Headers]
                VAR HeaderItems = SUBSTITUTE ( HeaderString, ",", "|" )
                VAR DetailString = [@Details]
                VAR DetailItems = SUBSTITUTE ( DetailString, ",", "|" )
                VAR Length = PATHLENGTH ( HeaderItems )
                VAR T4 = GENERATESERIES ( 1, Length, 1 )
                RETURN
                    FILTER ( 
                        SELECTCOLUMNS ( 
                            T4, 
                            "@Header", PATHITEM ( HeaderItems, [Value] ),
                            "@Detail", PATHITEM ( DetailItems, [Value] ) 
                        ),
                        [@Header] = "'Table'[" & XColumn & "]" 
                    )
            )
        RETURN
            MAXX ( T3, VALUE ( [@Detail] ) )
    )
RETURN
    Slope * X + Intercept