Hi I am using a a set of lookup functions etc to drag data from an excel table and filter it based on some inputs. The results are then used in my calculation. It is not necesarry to see the lookup functions in the calculation and I am trying to hide them from view. I would use hidden areas but I will be feeding data into the sheet using the API and this is not compatible with the hidden areas (i.e. I am not able to define any of the hidden variables). Instead, I am trying to create a 'summary sheet' which references the sheet containing the calculations, and extracts the meaningful values from it. This means I can update the lookups using the API, then open the summary sheet and tell it to recalculate. I am having some problems with referencing the worksheet. I can extract simple set values from the referenced worksheet (e.g. REF Sheet -> T:=50, Summary Sheet -> T=50) but I am having problems extracting anything that depends on a function or programming loop. Is this a limitation in mathcad, or is there a way around it? Cheers Jamie
