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SAM190370's avatar
SAM190370
Frequent Visitor
9 years ago
Solved

cursive calculation forecast

Hi,

 

Can I do something like this in dax or powerquery?

 

The formular should calculate the forecast using previous months sales and previous month forecast.  If no sales in previous month it should use forecast. I have tried to illustrate it below.

 

 

 

ImkeF, I know you have done something very similar to this https://www.mrexcel.com/forum/power-bi/948513-conditional-recursive-calculation-%5bneed-help%5d.html so maybe you can see the light? I tried to use generate.list, but dit manage to go all the way.

 

Hope you can assist me.

Need Help
  • ImkeF's avatar
    ImkeF
    9 years ago

    This might work:

     

    let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjQwMFCK1QEyjGAMUyjDCCalgI2MBQA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Sales = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Sales", type number}}),
    AddIndex = Table.Buffer(Table.AddIndexColumn(#"Changed Type", "Row", 1, 1)),
    ListGenerate = List.Generate(()=> 
        [Counter=1, Forecast=AddIndex[Sales]{0}],
        each [Counter] <=Table.RowCount(AddIndex),
        each [Forecast = if AddIndex{[Row=Counter]}[Sales]<>null then [Forecast]*0.7+AddIndex{[Row=Counter-1]}[Sales]*0.3 else [Forecast],
        Counter = [Counter]+1
        ]
    ),
    Forecast = Table.FromRecords(ListGenerate),
    #"Merged Queries" = Table.NestedJoin(AddIndex,{"Row"},Forecast,{"Counter"},"Forecast.1",JoinKind.LeftOuter),
    #"Expanded Forecast.1" = Table.ExpandTableColumn(#"Merged Queries", "Forecast.1", {"Forecast"}, {"Forecast"})
in
    #"Expanded Forecast.1"

7 Replies

  • kaushikd's avatar
    kaushikd
    Resolver II
    9 years ago

    Hi SAM190370

     

    This is possible in DAX, you just have to add a calculated column

    Step 1. R.Click on the table and click New column

    Step 2. In the Formula bar just add this Dax code---->Column 1 = IF('Sample'[Sales],'Sample'[Sales],'Sample'[Forecast])

     

    You can also do other calculation if required.

     

    if this is what you required then dont forget to like this post.

     

    • SAM190370's avatar
      SAM190370
      Frequent Visitor
      9 years ago

      kaushikdThanks for giving it a shot!

       

      Not exactly what I am looking for, but I guess I haven't been clear enough when creating the post. The trick is that I want to create the calculation of column B using DAX. 

      • ImkeF's avatar
        ImkeF
        Community Champion
        9 years ago

        This might work:

         

        let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjQwMFCK1QEyjGAMUyjDCCalgI2MBQA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Sales = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Sales", type number}}),
    AddIndex = Table.Buffer(Table.AddIndexColumn(#"Changed Type", "Row", 1, 1)),
    ListGenerate = List.Generate(()=> 
        [Counter=1, Forecast=AddIndex[Sales]{0}],
        each [Counter] <=Table.RowCount(AddIndex),
        each [Forecast = if AddIndex{[Row=Counter]}[Sales]<>null then [Forecast]*0.7+AddIndex{[Row=Counter-1]}[Sales]*0.3 else [Forecast],
        Counter = [Counter]+1
        ]
    ),
    Forecast = Table.FromRecords(ListGenerate),
    #"Merged Queries" = Table.NestedJoin(AddIndex,{"Row"},Forecast,{"Counter"},"Forecast.1",JoinKind.LeftOuter),
    #"Expanded Forecast.1" = Table.ExpandTableColumn(#"Merged Queries", "Forecast.1", {"Forecast"}, {"Forecast"})
in
    #"Expanded Forecast.1"