VAMPHI


VAMPHI is a variant of  program  AMPHI  for  use  with  VLBMEM.   VLBMEM
produces  a  "mock  data"  file  that  contains  the predicted ("model")
visibilities corresponding to the MEM image.   VAMPHI  uses  this  file,
instead  of a standard model file, to estimate complex antenna gains and
correct  the  visibilities  in  a  MERGE-format   file.    To   make   a
self-calibrated  image using VLBMEM instead of INVERT and CLEAN, use the
program sequence:  AMPHI with  starting  model  (e.g.,  point  source?);
VLBMEM to get trial image and mock data; VAMPHI to adjust amplitudes and
phases; VLBMEM to get new mock data; iterate....

     Control  parameters  are  the  same  as  for  AMPHI,  except   that
parameters  relating  to  the  input  model  (MODFILE,  XCG, YCG, CGNUM,
NCPRINT, NUMBER, NOLOOKUP) are not accepted:  use the MOCKDATA parameter
instead to specify an input mock data file.  The mock data file contains
the name of the associated merge file, so the  parameter  INPUT  is  not
required.

     It is intended that the functionality of VAMPHI will be included in
a future version of AMPHI.


Parameters

Important parameters are MOCKDATA,  OUTPUT,  LISTFILE  and  the  control
parameters  SCALE,  CLAMP,  etc.   See  the  AMPHI  help  file  for more
information.


History

Version 1.0:  1989 Dec 11:  derived from AMPHI v8.3 (TJP).
Version 1.1:  1990 Dec 12:  corrected for Sun Fortran (TJP).