meta_volume vs volume
Space.weight methods use volume instead of meta volume. Isn't this choice arbitrary? By excluding pixes from the weight that contain no new information, we weight according to the 'information volume' instead with the 'geometrical volume'. Also: LMspace (at least for real signal space partners) stores only one half of the pair-wise complex conjugated numbers, RGSpace with complexity==1 stores the full thing. The inner dot product treats them differently.
Definition of meta-volume: The meta volumes are the volumes associated with each component of a field, taking into account field components that are not explicitly included in the array of field values but are determined by symmetry conditions.