I have a product structure. The mass properties for the 3D Part leaf nodes are partially completed. Some are computed, some are declared.

I would like to filter the product structure to show only the items that do not have a declared mass, nor a computed mass.

In my search so far, there are "Computed Characteristics" and "Declared Mass" extensions for Physical Products, both with "Mass" attributes. I haven't had success combining expert filter inputs that use an attribute from more than one extension.

What's the most elegant way (or *an* elegant way) to write the filter that shows items that has neither a declared nor computed mass?

Thanks for the advice!

(Update): complicating the issue, perhaps, is that those attributes are not present on objects that do not have a declared mass or computed mass. So I cannot filter on those attributes.

A more general question: "can I filter a structure based on the *presence* of an attribute, rather than the attribute's *value*?"