Forum Discussion

jimmyhua's avatar
jimmyhua
Icon for Helper I rankHelper I
1 year ago
Solved

use List.Generate to create a conditional index gave me Expression.Error

I tried to create a conditional index for another list I created. here is the code I wrote and error I got.  The first list is to create a position indicator where the index can began. The first one ...
Need Help
  • Omid_Motamedise's avatar
    Omid_Motamedise
    1 year ago

    use the below formula

    let
    Source = {1,1,2,3,1,2,1,2,3,4,5,1,2,3,1,1,2},
    Custom1 = List.Transform(List.Positions(Source), each if Source{_}=1 then _+1 else null)
in
    Custom1

    result in 

     

     

     

lbendlin's avatar
lbendlin
Icon for Super User rankSuper User
1 year ago

Occurrence.All will create a list.

jimmyhua's avatar
jimmyhua
Icon for Helper I rankHelper I
1 year ago

yes.  i do want a list because there are multiple 1s in the first list.  want i want to do is first to find the positions of the 1s then create fill in nulls in between each position so i can fill down and group them together.  is there a way to do it?

  • lbendlin's avatar
    lbendlin
    Icon for Super User rankSuper User
    1 year ago

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

    Do not include sensitive information. Do not include anything that is unrelated to the issue or question.

    Need help uploading data? https://community.fabric.microsoft.com/t5/Community-Blog/How-to-provide-sample-data-in-the-Power-BI-Forum/ba-p/963216

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

    Want faster answers? https://community.fabric.microsoft.com/t5/Desktop/How-to-Get-Your-Question-Answered-Quickly/m-p/1447523

    • jimmyhua's avatar
      jimmyhua
      Icon for Helper I rankHelper I
      1 year ago

      here is sample list1, which represents a column in a table that I need to group. each 1 starts a new group.  I use List.PositionOf to find out the positions where each group starts.  Then I want to fill in nulls and use fill down to fill the spaces.  I will use the new index column to group the entire table.
      {1,1,2,3,1,2,1,2,3,4,5,1,2,3,1,1,2}

      • slorin's avatar
        slorin
        Icon for Super User rankSuper User
        1 year ago

        Hi jimmyhua 

        "here is sample list1, which represents a column in a table that I need to group. each 1 starts a new group."

         

        You can use Table.Group directly

         

        = Table.Group(
          YourSource,
          {"YourColumn"},
          {{"Data", each _}},
          GroupKind.Local,
          (x,y) => Byte.From(y[YourColumn]=1)
        )

         Stéphane