Roll up 1 column using function in DAX

Question

I am trying to roll up a table in DAX as seen below. It's just some operations. I can do this in SQL with joins or in Power Query with merges or pivots, however I was just wondering if this is possible using DAX. Would this even be a good idea? Would it better to perform such an operation using SQL/Power Query/Python/R?

name	type	quantity
t1	a	5
t1	b	10
t1	c	5
t2	a	5
t2	b	5
t2	c	10

f : (a + b)/c

name	quantity
t1	15/5
t2	10/10

Answer 1

This is a perfectly fine and simple calculation for DAX.

F = DIVIDE( CALCULATE( SUM('Table'[quantity]),'Table'[type] IN {"a","b"}),
            CALCULATE( SUM('Table'[quantity]),'Table'[type] = "c") )

Always use DIVIDE when there is a chance that the divisor ("c") could be 0. Use SUM just like you would in Excel, but wrap it in a CALCULATE if you need to filter values first. Use IN if you have a list of values to filter for the same column.