[CLEAN\]SUPPORT /MASK or [ADVANCED\]MASK USE
Use the mask defined by READ MASK or by the MASK command as the clean
support. This does not suppress the current polygon: it can be re-in-
stated by a simple SUPPORT command with no argument.
The Mask can be a 3-D array: CLEAN will find out which mask plane must
be used for each spectral channel.
Caution: [CLEAN\]READ MASK and [ADVANCED\]MASK command do not perform an
implicit SUPPORT /MASK command. Only the ADVANCED\MASK USE command does
it explicitely.
Gildas manager
2023-06-01