How to calculate length of series

[Denis_Slav]

Hi all,

I'd like to know how many times was value greater then 0 and get this value in last record for each series. 

ID	Raw	Length
1	1
2	1	2
3	-1
4	-1
5	-1
6	-1
7	1	1
8	-1
9	1
10	1	2

Table sorted by ID. 

How can i calculate it?

[v-janeyg-msft · Accepted solution]

Hi, @Denis_Slav 

According to your description, this problem seems simple, but it is actually difficult. You can try to create a custom column in PQ.

Like this(PQ advanced editor):

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUdI1VIrViVYyQjCNgUwIywQhaAoXNIOzzBHSFnBBSzjL0ADCjAUA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t, Raw = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"ID", Int64.Type}, {"Raw", Int64.Type}}),
    Custom1 = Table.Group(#"Changed Type","Raw",{"Test",each _},0,(x,y)=>Number.From(x*y<0)),
    #"Added Custom" = Table.AddColumn(Custom1, "Custom", each if [Raw]=-1 
then null 
else if [Raw]=1
then Table.RowCount([Test])
else null),
    Custom2 = Table.TransformRows(
   #"Added Custom",
   each let mtest=Table.Max( _[Test],"ID")[ID],cst=_[Custom]
   in
   [Raw=_[Raw],Test=Table.AddColumn(_[Test],"Re",(x)=>if x[ID]=mtest then _[Custom] else null)]
),
    #"Converted to Table" = Table.FromList(Custom2, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
    #"Expanded Column1" = Table.ExpandRecordColumn(#"Converted to Table", "Column1", {"Raw", "Test"}, {"Column1.Raw", "Column1.Test"}),
    #"Expanded Column1.Test" = Table.ExpandTableColumn(#"Expanded Column1", "Column1.Test", {"ID", "Raw", "Re"}, {"Column1.Test.ID", "Column1.Test.Raw", "Column1.Test.Re"}),
    #"Removed Columns" = Table.RemoveColumns(#"Expanded Column1.Test",{"Column1.Test.Raw"}),
    #"Reordered Columns" = Table.ReorderColumns(#"Removed Columns",{"Column1.Test.ID", "Column1.Raw", "Column1.Test.Re"}),
    #"Renamed Columns" = Table.RenameColumns(#"Reordered Columns",{{"Column1.Test.ID", "ID"}, {"Column1.Raw", "Raw"}, {"Column1.Test.Re", "Count1"}})
in
    #"Renamed Columns"

If it doesn’t solve your problem, please feel free to ask me.

Best Regards

Janey Guo

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

[Denis_Slav]

@v-janeyg-msft Thank you. I think it's great idea to group around [Raw] and count its lengrth. 

I'll try to use this logic in my report.

Thank you. 

[v-janeyg-msft]

Hi, @Denis_Slav 

Here is a solution with Dax. Also thanks my colleague @v-alq-msft.

Column = 
IF(
    [Raw]=-1,
    BLANK(),
    IF(
        [Raw]=1,
        var first = 
            CALCULATE(
                MAX('Table'[ID]),
                FILTER(
                    ALL('Table'),
                    [ID]<EARLIER('Table'[ID])&&
                    [Raw]=-1
                )
            )
        var f1 = 
        IF(
            ISBLANK(first),
            1,
            first+1
        )
        var last = 
            CALCULATE(
                MIN('Table'[ID]),
                FILTER(
                    ALL('Table'),
                    [ID]>EARLIER('Table'[ID])&&
                    [Raw]=-1
                )
            )
        var l1 = 
        IF(
            ISBLANK(last),
            MAX('Table'[ID]),
            last-1
        )
        return
        IF(
           [ID]=l1,
           l1-f1+1,
           BLANK()
        )
    )
)

Best Regards

Janey Guo

[parry2k]

@Denis_Slav I will find another way to tweak it but for now, add this measure and see if you get the result

Count = 
VAR  __currentId = MAX ( Series[ID] )
VAR __lastPostiiveId = CALCULATE ( MAX ( Series[ID] ), FILTER ( ALL ( Series ), Series[ID] < __currentId && Series[Raw ] > 0 ) )
VAR __nextPositiveId = CALCULATE ( MIN ( Series[ID] ), FILTER ( ALL ( Series ), Series[ID] > __currentId && Series[Raw ] > 0 ) )
VAR __checkNextPositiveId = __nextPositiveId <> __currentId + 1
VAR __startId = IF ( __lastPostiiveId <> __currentId - 1, __currentId, __lastPostiiveId )
VAR __result = 
IF ( 
    MAX ( [Raw ] ) > 0 && 
    NOT ISBLANK ( __lastPostiiveId ) && 
    __checkNextPositiveId, 
    COUNTROWS ( GENERATESERIES ( __startId, __currentId ) ) 
)
RETURN __result

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[Denis_Slav]

@parry2k Unfortunatly it's not work correct. I change values in [Raw], and they give me maximum 2, when it should be 4 values. 

And I try to make this calculation in column, not in measure.