Find beginning date/time and end date/time, calculate difference from another column

[blaferriere]

Hello,

So I am not sure if the title worded it correctly but I have a dataset that takes snapshots of dates in time and also captures other metrics for fuel burn. The problem that I run into is that it is accumulating the fuel burn amount throughout the history of the item.

My goal would be to capture how much fuel was burned for that particular day by taking the beginning date/time and the end date/time and then grab the difference in idle time and idle fuel.

For example, for 12/7 the daily idle time was 20356.88(from module time: 12/7/2018 10:49:53 PM) - 20355(12/7/2018 12:02:54 AM) = 1.88 for Daily Idle Fuel

If anyone could point me in the right direction with a link to a solution or provide me with the correct solution to put in to create this column that would be perfect, thank you all for your help!

[AlB]

Hi @blaferriere

Try this for the fuel calculate column. I'm not sure whether you need the same with the Idle Time as well? If you do, you can just make a minor change to the code below with Table1[Idle time] instead of Table1[Idle fuel] 

FuelDifference =
VAR _CurrentDateValues =
    CALCULATETABLE (
        VALUES ( Table1[Module Time] ),
        FILTER (
            Table1,
            Table1[Module Time].[Date] = EARLIER ( Table1[Module Time].[Date] )
        )
    )
VAR _EarliestDateTime =
    FIRSTNONBLANK ( _CurrentDateValues, 1 )
VAR _LatestDateTime =
    LASTNONBLANK ( _CurrentDateValues, 1 )
VAR _EarliestFuel =
    LOOKUPVALUE ( Table1[Idle fuel], Table1[Module Time], _EarliestDateTime )
VAR _LatestFuel =
    LOOKUPVALUE ( Table1[Idle fuel], Table1[Module Time], _LatestDateTime )
RETURN
    _LatestFuel - _EarliestFuel

[blaferriere]

Hi @AlB

It appears I am getting an error of circular dependency when I input the formula.

Thank you

[AlB]

@blaferriere

Do you have another calculated column in that table that has a CALCULATE or that uses measures?

Can you share the pbix?

[blaferriere]

@AlB

There are no calculations in the file.

Here is the link.

PBIX File

[AlB · Accepted solution]

@blaferriere

We need to make two changes.

1. The 'Module Time' column is currently text in your table. It needs to be of the type Date/Time. You can change the type in the query editor when importing the data (I see you're getting the data from an excel file)

2.  This is the reviewed code for the column, where I've just added the ALL( ) in red:

FuelDifference =
VAR _CurrentDateValues =
    CALCULATETABLE (
        VALUES ( Table1[Module Time] ),
        FILTER (
            ALL(Table1),
            Table1[Module Time].[Date] = EARLIER ( Table1[Module Time].[Date] )
        )
    )
VAR _EarliestDateTime =
    FIRSTNONBLANK ( _CurrentDateValues, 1 )
VAR _LatestDateTime =
    LASTNONBLANK ( _CurrentDateValues, 1 )
VAR _EarliestFuel =
    LOOKUPVALUE ( Table1[Idle fuel], Table1[Module Time], _EarliestDateTime )
VAR _LatestFuel =
    LOOKUPVALUE ( Table1[Idle fuel], Table1[Module Time], _LatestDateTime )
RETURN
    _LatestFuel - _EarliestFuel

Code formatted with  

[blaferriere]

@AlB

No Dice, throwing a syntax error.

[AlB]

@blaferriere

just edited my previous post. Forgot to mention the required type change

[blaferriere]

@AlB

I am still getting a syntax error. I made the changes to the Module Time to be Date/Time and applied the query. I also added the All to the details, with no luck.

[AlB]

@blaferriere

What syntax error? It's working on my side

[blaferriere]

@AlB

It's saying that the following:

The syntax for 'table' is incorrect. (DAX(VAR _CurrentDateValues = CALCULATETABLE ( VALUES ( table[Module Time] ), FILTER ( ALL(table), table[Module Time].[Date] = EARLIER ( table[Module Time].[Date] ) ) )VAR _EarliestDateTime = FIRSTNONBLANK ( _CurrentDateValues, 1 )VAR _LatestDateTime = LASTNONBLANK ( _CurrentDateValues, 1 )VAR _EarliestFuel = LOOKUPVALUE ( table[Idle fuel], table[Module Time], _EarliestDateTime )VAR _LatestFuel = LOOKUPVALUE ( table[Idle fuel], table[Module Time], _LatestDateTime )RETURN _LatestFuel - _EarliestFuel)).

[AlB]

@blaferriere

Use 'table'  (between single quotes) instead of table

Table is a reserved keyword

[blaferriere]

@AlB

Fantastic! You solved it! Thank you very much!

[AlB]

@blaferriere

Cool. Perhaps some kudos would be appropriate then after so much  back and forth?