Calculate the difference in minutes between lines

[ANB_13]

Good morning,
I need your help,

I am working on a dataset with a [Date] column in Date & Time format. as following :

I want to create a new column which calculates the difference for successive rows. The result of the 5 new lines should be:
5. How can i do ?

Thank you very much 

Regards

[amustafa]

Watch this video to learn Power Query Advance Editor where you paste the code.

Best Practice Tips For Using The Advanced Editor In Power BI [2022 Update] (youtube.com)

[AlienSx]

@dufoq3 this must be accompanied by v3 with list shift 😁

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjDSNzDUNzIwMlYwtzIwVYrVQRMzNMQUMzJDF7O0MjZSio0FAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t]),
    dt = Table.TransformColumnTypes(Source,{{"Date", type datetime}}),
    diff_lst = List.Buffer(List.Zip({dt[Date], {List.First(dt[Date])} & List.RemoveLastN(dt[Date], 1)})),
    diff_col = List.Transform(diff_lst, (x) => Duration.Minutes(x{0} - x{1})),
    tbl = Table.FromColumns(Table.ToColumns(dt) & {diff_col}, Table.ColumnNames(dt) & {"diff"})
in
    tbl

[dufoq3]

Hi @ANB_13,

You can find 2 versions of code here:

//Calculate the difference in minutes between lines
//https://community.fabric.microsoft.com/t5/Power-Query/Calculate-the-difference-in-minutes-between-lines/m-p/3670461#M120753

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjDSNzDUNzIwMlYwtzIwVYrVQRMzNMQUMzJDF7O0MjZSio0FAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type datetime}}),
    v1_Slower_AddedIndex = Table.AddIndexColumn(#"Changed Type", "Index", 0, 1, Int64.Type),
    v1_Slower_Difference = Table.RemoveColumns(Table.AddColumn(v1_Slower_AddedIndex, "Difference d:hh:mm:ss", each try [Date] - v1_Slower_AddedIndex{[Index]-1}?[Date] otherwise null, type duration), {"Index"}),
    v2_Faster_Difference = 
        Table.RenameColumns(
            Table.FromRecords(
                [timesList = List.Buffer(#"Changed Type"[Date]),
                lg = 
                    List.Generate(
                        ()=>  [ x = 0, DateTime = timesList{0}, Difference = null ],
                        each  [x] < List.Count(timesList),
                        each  [ x = [x]+1, DateTime = timesList{x}, Difference = DateTime - [DateTime] ],
                        each  [ [DateTime], [Difference] ]
                    )
                ][lg],
                type table[DateTime = datetime, Difference = duration]
            ),
            {{"DateTime", "Date Time"}, {"Difference", "Difference d:hh:mm:ss"}}
        )
in
    v2_Faster_Difference

[ANB_13]

Good morning, 

Where do i use this code ? 

Thank you 

[amustafa · Accepted solution]

Hi, create a blank query and paste the following code to see how you can create a calulated column for minutes lapsed between rows.

let
StartDateTime = #datetime(2024, 1, 1, 0, 0, 0),
EndDateTime = #datetime(2024, 1, 2, 0, 0, 0),
DurationInMinutes = 5,
Source = List.Generate(
() => StartDateTime,
(DateTime) => DateTime < EndDateTime,
(DateTime) => DateTime + #duration(0, 0, DurationInMinutes, 0)
),
TableFromList = Table.FromList(Source, Splitter.SplitByNothing(), {"DateTime"}),
ChangedType = Table.TransformColumnTypes(TableFromList, {{"DateTime", type datetime}}),
SortedTable = Table.Sort(ChangedType, {{"DateTime", Order.Ascending}}),
AddIndex = Table.AddIndexColumn(SortedTable, "Index", 0, 1, Int64.Type),
AddMinutesLapsed = Table.AddColumn(AddIndex, "Minutes Lapsed", each if [Index] = 0 then 0 else Duration.TotalMinutes([DateTime] - (AddIndex{[Index]-1}[DateTime])), type number)
in
AddMinutesLapsed

If I answered your question, please mark this thread as accepted and Thums Up!
Follow me on LinkedIn:
https://www.linkedin.com/in/mustafa-ali-70133451/