Can RANK function be used anywhere other than the WITH clause - mdx

Question

In a previous post I had this script:
WITH
SET [orderedSet] AS
ORDER(
[Operator].members,
[Operator].currentmember.name,
BASC
)
MEMBER [Measures].[newMeasure] AS
RANK(
[Operator].currentmember,
[orderedSet]
)
SELECT
[Measures].[newMeasure] ON COLUMNS,
[orderedSet] ON ROWS
FROM [ourCube]
Plus further reference to the MSDN page
Can the RANK function be used in any clauses other than WITH?
It's first argument is a tuple so I'm not sure how to use it in other clauses such as the SELECT.

Answer 1

It can be used anywhere where a numeric expression can be used.
Please note that in MDX, the axes in the select clause are sets, hence you cannot use Rank or any function that returns a numeric expression in an axis clause, but only functions returning sets (or some data types like tuples which are implicitly converted to sets).
And all members that appear in an expression returning a set have to be defined before you start with this expression. Hence, you cannot define them in the axis clause like you can use expressions to define result columns in SQL selects.
However, to literally answer your question, you can use Rank indirectly in the select clause in MDX e. g. if the outer function is Filter, which returns a set. The following is a slightly inefficient way to show the first three countries according to attribute order:
SELECT {[Measures].[Internet Sales Amount]}
ON COLUMNS,
Filter(
[Customer].[Customer Geography].[Country].Members as C,
Rank(C.Current, [Customer].[Customer Geography].[Country].Members) <= 3
)
ON ROWS
FROM [Adventure Works]
Some people use Rank within Generate to reverse sets, which would be another use of Rank that would be legal in the select clause.