Compute the integrated flux from the CLEAN image, using zones defined either by calling the Cursor, or by the current Support, or by the current Mask.
If the CLEAN data is a 3-D cube, the integrated flux will be a spectrum.
For FLUX MASK, if the Mask defines several separate zones, an integrated flux will be computed for each zone. Zones are ordered by decreasing number of pixels.
The FLUX results are available in the FLUX SIC structure, and can be displayed by SHOW FLUX and also SHOW COMPOSITE.