Power Pivot - calculated fields

Hi I am trying to add an explicit calculated field to Powerpivot which looks up an implicit calculated field in a lookup table and gives the result. Is this possible?

Many thanks for any help

Tom

A sample file would better illustrate what you're trying to accomplish. May also want to check out the function below, in case that helps with what you're trying to accomplish.

http://office.microsoft.com/en-us/ex...in=HP010342656