DAX forLoop

[smpa01]

@AlexisOlson  is it possible to replicate a forLoop in DAX. I need a forLoop that works in filter context. I am not able to find anything that can do the following in DAX.

let
   src=Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("Jcu5DQAxDAPBXhg7kHR+axHcfxsn0gmBHYCZMDS4r9o1cFvCBbs2HoTg1E71xw7+urqreTsmGALd7MmU8BiU+wM=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [index = _t, row = _t, Value = _t]),
    ct = Table.TransformColumnTypes(src,{{"index", Int64.Type}, {"row", Int64.Type}, {"Value", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(ct, "Custom", each let
 curr = [index],
 filt = Table.SelectRows(ct, (_)=> (_[index] >= curr)),
 terminator = Table.RowCount(filt)-1,
 forLoop = List.Generate(
     ()=> [ i =0, x = filt[Value]{i}, y= Text.From(filt[row]{i}), combins = 0+x],       
        each [combins]<=100,
        each [i=[i]+1, x= filt[Value]{i}, y= [y]&"-"&Text.From(filt[row]{i}), combins = [combins]+x],
        each [y]
 ),
 len = List.Count(forLoop)-1
 in if (len>=0) then forLoop{len} else null)
in
    #"Added Custom"

Thank you in advance.

[smpa01]

Great, but how do I apply this to my scenario is the challenge. I need a for Loop to work in a way so that for each row in the filter context it considers a table where filter(all(table), table[index]>= currentIndexVisible) and then keep on conctaenating table[row], till runningTotal of values <=100 (termination clause).

[lbendlin]

Please provide sample data that covers your issue or question completely, in a usable format (not as a screenshot).

Do not include sensitive information or anything not related to the issue or question.

Please show the expected outcome based on the sample data you provided.

[smpa01]

You can use the code from snippet to get the sample data.

[lbendlin · Accepted solution]

Custom DAX =
VAR i = [index]
VAR b =
    ADDCOLUMNS (
        FILTER ( Query1, [index] >= i ),
        "g",
            VAR i2 = [index]
            RETURN
                SUMX ( FILTER ( Query1, [index] >= i && [index] <= i2 ), [Value] )
    )
RETURN
    CONCATENATEX ( FILTER ( b, [g] <= 100 ), [row], "-" )

[lbendlin]

Here's a slightly optimized version

Custom DAX = 
VAR i = [index]
VAR f =
    FILTER ( Query1, [index] >= i )
VAR g =
    ADDCOLUMNS (
        f,
        "rt", VAR i2 = [index] RETURN SUMX ( FILTER ( f, [index] <= i2 ), [Value] )
    )
RETURN
    CONCATENATEX ( FILTER ( g, [rt] <= 100 ), [row], "-" )

[lbendlin]

All iterator functions are For Loops in DAX. SUMX, MAXX, PRODUCTX etc. One could argue that SUMMARIZE, SUMMARIZECOLUMNS and GENERATE are For Loops too.