Forum Discussion

rbartlejr's avatar
rbartlejr
Helper III
6 years ago
Solved

Problems with MTBF calculations

I've been trying to emulate the MTBF calculations in this blog post: https://community.powerbi.com/t5/Community-Blog/Mean-Time-Between-Failure-MTBF-and-Power-BI/ba-p/339586. I'm having problems with the Dax formulas in it. For example, the author shows:

Uptime =

VAR next = MINX(FILTER(Repairs,

                       Repairs[MachineName]=EARLIER(Repairs[MachineName]) &&

                       Repairs[RepairStarted]>EARLIER(Repairs[RepairStarted]) &&

                       Repairs[RepairType]<>"PM"

               ),Repairs[RepairStarted])

RETURN IF([RepairType]="PM", 0,IF(ISBLANK(next),

               DATEDIFF([RepairCompleted],NOW(),SECOND),

               DATEDIFF([RepairCompleted],next,SECOND)

           )

       )

 

I modified it to my data and get this:

Uptime =

VAR next = MINX(FILTER(Repairs,

          Repairs[Asset #]=EARLIER(Repairs[Asset #]) &&

          Repairs[DateIn]>EARLIER(Repairs[DateIn]) &&

          Repairs[comments]<>"Return to bin"

          ),Repairs[DateIn].[Day])

RETURN IF(Repairs[comments]="Return to bin", 0,IF(ISBLANK(next),

          DATEDIFF([DateOut],NOW(),DAY),

           DATEDIFF([DateOut],next,Day)

     )
)

 

I get this error: The syntax for ',' is incorrect. (DAX(VAR next = MINX(FILTER(Repairs, Repairs[Asset #]=EARLIER(Repairs[Asset #]) && Repairs[DateIn]>EARLIER(Repairs[DateIn]) && Repairs[comments]<>"Return to bin" ),Repairs[DateIn].[Day])RETURN IF(Repairs[comments="Return to bin", 0,IF(ISBLANK(next), DATEDIFF([DateOut],NOW(),DAY), DATEDIFF([DateOut],next,Day) ) ))).

 

I also get red  underlines under all of the columns next to EARLIER and DATEDIFF. Anyone have any ideas?

 

  • Looks like you are missing a comma or semi-colon after the VAR next line.
  • rbartlejr's avatar
    rbartlejr
    6 years ago

    Yes! I was missing the comma. BTW I just bought your book. Thanks for your help!

9 Replies

  • Greg_Deckler's avatar
    Greg_Deckler
    Community Champion
    Sounds like you need to change the commas to semi-colons ( ; ). Regional language settings.
    • rbartlejr's avatar
      rbartlejr
      Helper III

      Greg_Deckler Ok, I tried that and get this error: EARLIER/EARLIEST refers to an earlier row context which doesn't exist. I looked in the data and there are more than one asset #s in several rows.

      • Greg_Deckler's avatar
        Greg_Deckler
        Community Champion
        And is this a column you are creating? It should be a column and not a measure if I remember correctly.