Elegant way to ignore null when applying RANK - mdx

Question

This article gives a method for ignoring null when applying RANK : http://www.bidn.com/blogs/CraigLove/ssas/2617/mdx-walkthrough
Is there a more elegant way of doing this than using CASE ?
WITH
MEMBER [Measures].[City Rank]
AS
CASE
WHEN
NOT ISEMPTY
(
(
[Geography].[City].CurrentMember
,[Measures].[Reseller Sales Amount]
)
)
THEN
RANK
(
[Geography].[City].CurrentMember
,[Geography].[City].AllMembers
,[Measures].[Reseller Sales Amount]
)
ELSE
NULL
END
SET [OrderedCity]
AS
ORDER
(
[Geography].[City].AllMembers
,[Measures].[Reseller Sales Amount]
,DESC
)
SELECT
{
[Measures].[City Rank]
,[Measures].[Reseller Sales Amount]
} ON COLUMNS
,NON EMPTY [OrderedCity] ON ROWS
FROM [Adventure Works];

Answer 1

You could apply the NonEmpty function within OrderedCity:
WITH
SET [OrderedCity]
AS
NonEmpty(
ORDER
(
[Geography].[City].AllMembers
,[Measures].[Reseller Sales Amount]
,DESC
)
)
MEMBER [Measures].[City Rank]
AS
RANK
(
[Geography].[City].CurrentMember
,[OrderedCity]
)
SELECT
{
[Measures].[City Rank]
,[Measures].[Reseller Sales Amount]
} ON COLUMNS
,[OrderedCity]
ON ROWS
FROM [Adventure Works];
This way the NON EMPTY is applied on the set on the rows before it it put there, so there is no need to apply it on the rows themselves. Furthermore, re-using the set within the definition of City Rank allows Analysis Services to calculate the sorting only once, and cache the ordered set. Otherwise, the Rank would require the ordering to be re- calculated for each row.