17.12.19      PRIMARY

SHOW PRIMARY [PLANE|FIELD Kn] [First Last]

Show some sub-cube of the (4-D) Primary Beams.

The 2nd argument indicates whether SHOW shows all Fields for a given frequency plane (PLANE keyword), or all Frequency-dependent beams for a given Field (FIELD keyword). The 2nd and 3rd arguments are optional if the beam is only 3-D, which occurs for a single field or a frequency-indepedent beam in Mosaics (narrow band approximation).