Understanding unit net effectivity

For a large and complex structure, it is useful to understand the net effectivity of components within the structure. A lower level component may have been originally specified for any effectivity or a large range, but a narrower range applied at a higher level in the structure can reduce the net range for that component line.

Unit net effectivity can be considered as the intersection of an occurrence’s unit occurrence effectivity with its parent’s calculated unit net effectivity, from the specified structure line up to the top of the structure. For a line without an underlying occurrence (top line of a structure), there is no occurrence effectivity. This line is considered unconstrained and always configured. The unit net effectivity of a line that has no unit occurrence effectivity is equivalent to its parent’s calculated unit net effectivity.

• If the line has only date effectivity expressions, these are ignored and the unit net effectivity is the same as its parent’s calculated net effectivity.

• If there are multiple unit effectivity expressions with the same end item, these expressions are merged before intersection with the parent’s calculated net effectivity.

• The intersection is taken with respect to the end item designations of the parent’s unit net effectivity expressions. Unit effectivity expressions whose end items do not match any in the parent’s unit net effectivity are ignored.

• If there is no intersection of the line’s unit occurrence effectivity and the parent’s unit net effectivity, the line’s unit net effectivity is set empty (fully constrained).

• The unit net effectivity of a line whose parent’s unit net effectivity is empty also has an empty unit net effectivity, regardless of the line’s unit occurrence effectivity.

• The unit net effectivity of a particular component line is calculated when you display the line and is not persisted in subsequent sessions.

Effectivity flow-down reporting helps the user understand effectivity ranges and the impact of changes, especially as the complexity of the effectivity increases through the structure.