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webbta's avatar
webbta
Regular Visitor
1 year ago
Solved

Requesting help to group events by time

I have about two years worth of data with several thousand IDs. I filtered this example to just show one ID but there are many 1,000. I want to group events on this table by two-hour intervals by ID.

I want to create a column that looks at the earliest time within a two-hour window. The screenshot below shows what the column would look like if I had the logic right. When two hours passes from the first time, the next times are then grouped with that earliest time and so on until the day changes.


I prefer to create this column in Power Query but I am open to using DAX as well. 

How do I do that? Thank you so much!!

  • Anonymous's avatar
    Anonymous
    1 year ago

    Hi webbta ,

    I create sample data myself, including different IDs and different days:

    Then you can put the whole M code below into the Advanced Editor:

    let
        Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ddBLDsMgDATQq0SsI8U/HJhduq/UfZT7X6OkpUgNYf3wePC+B+aFeBESm2iFCKJP2zPMYQvH/M8JlMFpxA4zKE+ve15hjtixVM7nbqNreGVmUAR31X5caivUB+En5/JitJsRS/P05UfHXj59VhuyKshHnMDxZlobR4LUo/ZsMAXn0bR/wu3K1ljWkt/Cjzc=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, ID = _t]),
        #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type datetime}, {"ID", type text}}),
        FillEarliestTime = (table as table) as table =>
            let
                ListOfRecords = Table.ToRecords(table),
                init = {List.First(ListOfRecords)[Date]},
                accFunc = (acc as list, curr as record) =>
                    let
                        lastTime = List.Last(acc),
                        duration = Duration.TotalMinutes(curr[Date] - lastTime)
                    in
                        if duration <= 120 then
                            acc & {lastTime}
                        else
                            acc & {curr[Date]},
                ListOfEarliestTimes = List.Accumulate(List.Skip(ListOfRecords, 1), init, accFunc),
                FilledTable = Table.FromColumns(Table.ToColumns(table) & {ListOfEarliestTimes}, Table.ColumnNames(table) & {"Earliest Time"})
            in
                FilledTable,
        #"Grouped Table" = Table.Group(#"Changed Type", {"ID"}, {{"GroupedTable", each FillEarliestTime(_), type table [Date=nullable datetime, ID=nullable text, Earliest Time=nullable datetime]}}),
        #"Expanded GroupedTable" = Table.ExpandTableColumn(#"Grouped Table", "GroupedTable", {"Date", "Earliest Time"}, {"Date", "Earliest Time"})
    in
        #"Expanded GroupedTable"

    And the final output is as below:


    Best Regards,
    Dino Tao
    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

  • Hi tw2024, that means your data are not sorted as you showed as in your sample. Try this one and let me know:

     

    let
        Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ddE9DoMwDAXgq6DMSPgvJnkb3St1R9z/Gg0tpYIk8xc/O/a6BuaJeBISG2iGCKIPyzOMYQnbeOUEyuDUY4cZlIdXm2eYI1YsB+e9t9E9/GBmUARXo/24jK1Q74TvnMuLXm9GLJOnLz8q9vLpfbQuq4K8xwkcG9V6ciTIsdSaDabg3Kv2T7jd2U6WueT3whPEGvfW/84v997e", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, ID = _t]),
        ChangedType = Table.TransformColumnTypes(Source,{{"Date", type datetime}, {"ID", type text}}, "en-US"),
        GroupedRows = Table.Group(ChangedType, {"ID"}, {{"All", each [
                // aDetail = GroupedRows{[ID="A"]}[All],
                aDetail = Table.Sort(_, {{"Date", Order.Ascending}}),
                aGroupedRows = Table.Group(aDetail, {"Date"}, {{"T", each Table.AddColumn(_, "Earliest Time", (x)=> Time.From([Date]{0}), type time), type table}}, 0,
                    (x,y)=> Byte.From( (y[Date] - x[Date]) >= #duration(0,2,0,0) ) ),
                aCombinedT = Table.Combine(aGroupedRows[T])
              ][aCombinedT], type table}}),
        CombinedAll = Table.Combine(GroupedRows[All])
    
    in
        CombinedAll

12 Replies

  • Please provide sample data that covers your issue or question completely, in a usable format (not as a screenshot).
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    Please show the expected outcome based on the sample data you provided.

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  • Hi webbta 

    This problem can be easily solve just by using the fifith argument of Table.Group

     

    copy the below code and past it into the advance editor to see its magic

    let
        Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ddBLDsMgDATQq0SsI8U/HJhduq/UfZT7X6OkpUgNYf3wePC+B+aFeBESm2iFCKJP2zPMYQvH/M8JlMFpxA4zKE+ve15hjtixVM7nbqNreGVmUAR31X5caivUB+En5/JitJsRS/P05UfHXj59VhuyKshHnMDxZlobR4LUo/ZsMAXn0bR/wu3K1ljWkt/Cjzc=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, ID = _t]),
        #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type datetime}}),
        #"Grouped Rows" = Table.Group(#"Changed Type", "Date", {{"Count", each _, type table [Date=nullable text, ID=nullable text]}},0,(a,b)=>Number.From((b-a)>#duration(0,2,0,0)))
    in
        #"Grouped Rows"

     

    • tw2024's avatar
      tw2024
      New Member



      This was the result for the above method - I wasn't able to see how to find the earliest time by ID and date.

  • webbta's avatar
    webbta
    Regular Visitor

    Thank you so much for answering! And I think I was sloppy with my first example and I messed up a cell or two. 

    An example would be a list of IDs with a timestamp. I want to create a calculated column that finds the earliest time in the previous two hours.

    If there is no time in the previous two hours, then that time becomes the new earliest time.

    The next photo with the Earliest Time column heading shows the expected output of the calculated column based on the logic I have in mind.



    • Anonymous's avatar
      Anonymous
      Not applicable

      Hi webbta ,

      I create sample data myself, including different IDs and different days:

      Then you can put the whole M code below into the Advanced Editor:

      let
          Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ddBLDsMgDATQq0SsI8U/HJhduq/UfZT7X6OkpUgNYf3wePC+B+aFeBESm2iFCKJP2zPMYQvH/M8JlMFpxA4zKE+ve15hjtixVM7nbqNreGVmUAR31X5caivUB+En5/JitJsRS/P05UfHXj59VhuyKshHnMDxZlobR4LUo/ZsMAXn0bR/wu3K1ljWkt/Cjzc=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, ID = _t]),
          #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type datetime}, {"ID", type text}}),
          FillEarliestTime = (table as table) as table =>
              let
                  ListOfRecords = Table.ToRecords(table),
                  init = {List.First(ListOfRecords)[Date]},
                  accFunc = (acc as list, curr as record) =>
                      let
                          lastTime = List.Last(acc),
                          duration = Duration.TotalMinutes(curr[Date] - lastTime)
                      in
                          if duration <= 120 then
                              acc & {lastTime}
                          else
                              acc & {curr[Date]},
                  ListOfEarliestTimes = List.Accumulate(List.Skip(ListOfRecords, 1), init, accFunc),
                  FilledTable = Table.FromColumns(Table.ToColumns(table) & {ListOfEarliestTimes}, Table.ColumnNames(table) & {"Earliest Time"})
              in
                  FilledTable,
          #"Grouped Table" = Table.Group(#"Changed Type", {"ID"}, {{"GroupedTable", each FillEarliestTime(_), type table [Date=nullable datetime, ID=nullable text, Earliest Time=nullable datetime]}}),
          #"Expanded GroupedTable" = Table.ExpandTableColumn(#"Grouped Table", "GroupedTable", {"Date", "Earliest Time"}, {"Date", "Earliest Time"})
      in
          #"Expanded GroupedTable"

      And the final output is as below:


      Best Regards,
      Dino Tao
      If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

      • webbta's avatar
        webbta
        Regular Visitor

        Dino, Thank you tremendously! Your solution worked for me and I was able to incorporate it into my pbx.

  • dufoq3's avatar
    dufoq3
    Community Champion

    Hi webbta, check this:

     

    Output

    let
        Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ddBLDsMgDATQq0SsI8U/HJhduq/UfZT7X6OkpUgNYf3wePC+B+aFeBESm2iFCKJP2zPMYQvH/M8JlMFpxA4zKE+ve15hjtixVM7nbqNreGVmUAR31X5caivUB+En5/JitJsRS/P05UfHXj59VhuyKshHnMDxZlobR4LUo/ZsMAXn0bR/wu3K1ljWkt/Cjzc=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, ID = _t]),
        ChangedType = Table.TransformColumnTypes(Source,{{"Date", type datetime}, {"ID", type text}}, "en-US"),
        GroupedRows = Table.Group(ChangedType, {"Date", "ID"}, {{"T", each Table.AddColumn(_, "Earliest Time", (x)=> Time.From([Date]{0}), type time), type table}}, GroupKind.Local,
            (x,y)=> Byte.From( (y[Date] - x[Date]) >= #duration(0,2,0,0) ) ),
        Combined = Table.Combine(GroupedRows[T])
    in
        Combined
    • tw2024's avatar
      tw2024
      New Member

      Hello! Thank you for responding. I tried this method but I was not able to get them to group properly because sometimes (using your example) the ID labeld B is mixed with the ID labeled A. So some of B will be before 2.11 and before 3.11 and the times are not showing properly for different ID types.

      • dufoq3's avatar
        dufoq3
        Community Champion

        Hi tw2024, that means your data are not sorted as you showed as in your sample. Try this one and let me know:

         

        let
            Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ddE9DoMwDAXgq6DMSPgvJnkb3St1R9z/Gg0tpYIk8xc/O/a6BuaJeBISG2iGCKIPyzOMYQnbeOUEyuDUY4cZlIdXm2eYI1YsB+e9t9E9/GBmUARXo/24jK1Q74TvnMuLXm9GLJOnLz8q9vLpfbQuq4K8xwkcG9V6ciTIsdSaDabg3Kv2T7jd2U6WueT3whPEGvfW/84v997e", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, ID = _t]),
            ChangedType = Table.TransformColumnTypes(Source,{{"Date", type datetime}, {"ID", type text}}, "en-US"),
            GroupedRows = Table.Group(ChangedType, {"ID"}, {{"All", each [
                    // aDetail = GroupedRows{[ID="A"]}[All],
                    aDetail = Table.Sort(_, {{"Date", Order.Ascending}}),
                    aGroupedRows = Table.Group(aDetail, {"Date"}, {{"T", each Table.AddColumn(_, "Earliest Time", (x)=> Time.From([Date]{0}), type time), type table}}, 0,
                        (x,y)=> Byte.From( (y[Date] - x[Date]) >= #duration(0,2,0,0) ) ),
                    aCombinedT = Table.Combine(aGroupedRows[T])
                  ][aCombinedT], type table}}),
            CombinedAll = Table.Combine(GroupedRows[All])
        
        in
            CombinedAll