For consistency reasons over all the commands in CLASS which can
make use of the weight array, its content is assumed to be inexistant
or unset when entering the command: the weight array is recomputed
each time it is needed. This implies a unique value for all the
channels, e.g. the value computed by BASE.
The discussions in this document raise the idea to save the weight array in the CLASS data format. Indeed, we have seen that the single value which is recomputed from scratch can not reflect the real weight of each channel, e.g. when the spectrum is the AVERAGE of several others in COMPOSITE mode. But this has two major caveats:
For small amount of data (e.g. with long integration times, line surveys,...), this would not be a problem. But when dealing with large quantity of data e.g. multibeam OTF observations, the increase would become dramatic. We may need in this case to have the choice to save or not the weight arrays.
For the time being, saving (always or not) the weight array in the CLASS data format remains an open question.