[daip] 'p!a' vs 'p' mode

[Eric Greisen]

Scott Hyman writes:
 > 
 > Hello,
 > 
 > I am curious as to the difference between the SOLMODE settings:  'p!a' and 'p'
 > 
 > I have use 'p' mode for "phase-only" self-calibration, but I just  
 > noticed that there is 'p!a' mode. Does 'p' mode use the amplitude  
 > information, after all?
 > 

The amplitudes enter into the P mode in that the full visibilities are
kept through the averaging and solutions.  In 'P!A' the visbilities
are translated into pure phases (amplitude 1) after averaging but
before any solutions.  In P mode, the amplitudes are present during
the gain solutions but only phase is retained or examined during
minimization.

Eric Greisen