Creating a measure in Dax to calculate difference between two rows (similar to excel)

[liamcol]

I would like to create a new column which would measure the difference between the two rows to find the "scan length"

What would be the DAX formula for this?  

Thanks!

[wdx223_Daniel]

new column=maxx(filter(table,table[Local Time]>earlier(table[Local Time])),table[Local Time])-table[Local Time]

[Nathaniel_C]

Hi @liamcol 
Try this:

Diff = 
var _curMeasure = MAX(myTable[Measure]) //This row's measure
var _curTime = MAX(myTable[Time])       //This row's time


var _calc = CALCULATE(MAX(myTable[Measure]),FILTER(ALL(myTable),myTable[Time]<_curTime))  //Get the measure of the previous row


return IF(_curMeasure-_calc=_curMeasure,0,_curMeasure-_calc)  //if there is no previous measure, then 0 else the diff

Let me know if you have any questions.

If this solves your issues, please mark it as the solution, so that others can find it easily. Kudos 👍are nice too.
Nathaniel

[liamcol]

I am unsure what to put for this rows measure? 

Thanks

[Nathaniel_C]

Hi @liamcol ,
As you did not supply us with a pbix, I created a quick table called myTable with the columns named Time and Measure. 

Let me know if you have any questions.

If this solves your issues, please mark it as the solution, so that others can find it easily. Kudos 👍are nice too.
Nathaniel