set analysis expression

[geogou1973]

Hello,

I have a field that has values like NA, NC, NZ and values null.

How can i take only the null values in an expression of set analysis ?

sum({<isnull(CSTAAR)>} [Stock Qty])    this does not work

sum({<CSTAAR={' '}>} [Stock Qty])        this does not work also.

please any help ?

Thank you in advance.

[geogou1973]

also with the flag i don't have the 5 lines that have 0,000 values

[sfatoux72]

Use this,  :

If(Sum({<CSTAAR=-{'NC','NA','NZ'}>} [Stock Qty]) = 0, 0, Null())