[CLEAN\]UV_STAT WEIGHT [Start [Step]]
For WEIGHT, beam sizes and noise level (in flux and brightness) will be
computed for 9 different "robust" weighting parameters (from Start to
Start*Step^9). Default value for Step is sqrt(10), and default value for
Start is derived to center the "robust" parameter values around 1. UV
cell size is taken from variable MAP_UVCELL, and Taper is taken from
variable UV_TAPER.