Dates comparison in sap analytics cloud

Friends

I am trying to compare 2 date dimensions to see the result value as "boolean" say True or False.

Context: say we have 2 date dimensions

1)Adate(MM-DD-YYYY)

2)Bdate(MM-DD-YYYY)

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Calculation/Comparision needed : If(Adate<=Bdate,"A" elsif Adate>Bdate then "B" else "NA")

Could you share your experiences...

Thanks-Bose