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Anonymous's avatar
Anonymous
Not applicable
3 years ago

Reference Previous Row Without Sorting & Index

Hi, I have a datasheet with a [depth] value, a [dollar] value, and a [category] value.   I would like to create a column that references the [dollar] value from the previous [depth] row, for each [...
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Anonymous's avatar
Anonymous
Not applicable
3 years ago

Anonymous Thanks for the quick response, I sure appreciate it. 

That's an interesting idea, but I'm not sure how multiple data flows would differ from a single data flow. Don't I have to perform the same transformations in the second data flow, which references the previous row from the first dataflow? 

Poohkrd's avatar
Poohkrd
Advocate I
3 years ago

Hi, it's differs a lot. And what algorithm you use after indexing your table? 

Try this one:

let
    Source = Table.FromColumns({{"a","b","c","d"}},{"col"}),
    col = List.Buffer({null}&Source[col]),
    AddedIndex = Table.AddIndexColumn(Source, "ind", 0, 1),
    TransformToPrevRow = Table.TransformColumns(AddedIndex, {{"ind", each col{_}}})
in
    TransformToPrevRow