question about using PreviousDay function

[LeeI]

I have a simple measure that is supposed to return the previous days number for a count of apps that meet a certain criteria. At first, I tried this dax expression: 

Apps previous day = Calculate(

                                                  count(data[app Number]), Previousday(date DIM [Date]))

This expression does not return an error, but it also does not return any values. I was able to get the measure to work properly by using:

Apps Previous Day =

CALCULATE(

    COUNT(Data[app Number]),

    FILTER(

        ALL('Date DIM'),

        'Date DIM'[Date] = Today() -1

    )

)

However, I am confused why the first dax expression does not work. Especially since Microsoft's publishing of the previousday function seems to imply that it should. 

https://learn.microsoft.com/en-us/dax/previousday-function-dax

Would anyone be able to help me understand why the first dax expression does not seem to be working properly? 

Thanks, 

[bhanu_gautam · Accepted solution]

@LeeI  , The PREVIOUSDAY function is a time intelligence function that works with a date column to return a table containing the previous day. However, it requires a proper date context to function correctly.

Try using ALL function to remove any existing filter on dim[date]

Apps previous day =
CALCULATE(
COUNT(data[app Number]),
PREVIOUSDAY(ALL('Date DIM'[Date]))
)