Incomplete child sets

hierarchy

A set intended to represent 'all children of parent X at resolution N' is missing one or more children (e.g. due to an upstream filter or antimeridian/pentagon edge case), silently under-covering the parent's area.

Detection

count(children in set) != len(cellToChildren(parent, N)) for the expected resolution.

Mitigation

Verify full child-set completeness against cellToChildren before compacting or delivering
Alert on any parent whose child coverage is partial rather than silently propagate a hole

Affected conversions

Cell system → cell system approximate