; OPCODE
;---------------------------------------------------------------
;! General adverb, defines an operation
;# ADVERB GENERAL UTILITY
;-----------------------------------------------------------------------
;;  Copyright (C) 1995
;;  Associated Universities, Inc. Washington DC, USA.
;;
;;  This program is free software; you can redistribute it and/or
;;  modify it under the terms of the GNU General Public License as
;;  published by the Free Software Foundation; either version 2 of
;;  the License, or (at your option) any later version.
;;
;;  This program is distributed in the hope that it will be useful,
;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;  GNU General Public License for more details.
;;
;;  You should have received a copy of the GNU General Public
;;  License along with this program; if not, write to the Free
;;  Software Foundation, Inc., 675 Massachusetts Ave, Cambridge,
;;  MA 02139, USA.
;;
;;  Correspondence concerning AIPS should be addressed as follows:
;;         Internet email: aipsmail@nrao.edu.
;;         Postal address: AIPS Project Office
;;                         National Radio Astronomy Observatory
;;                         520 Edgemont Road
;;                         Charlottesville, VA 22903-2475 USA
;-----------------------------------------------------------------------
;---------------------------------------------------------------
OPCODE    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
OPCODE
Type: Adverb (String*4)
Use:  To specify the operation to be used by a task or verb.
Null Value: '   ' has various meanings depending on the task.
      When '    ' is listed below, it means that the task gives
      some special meaning to OPCODE = '    ' or at least to
      any OPCODE value not in the list.

Verbs with supported OPCODE values:
  PUTVALUE...Store a pixel value at specified position in image:
             'BLNK', '    '

Procedures with supported OPCODE values:
  VLACLCAL...Run CLCAL and LISTR for VLA data:
             'MERG', 'CALI', 'SMOO'

Tasks with supported OPCODE values:
  APVC.......Deconvolve images with van Cittert algorithm:
             'VC  ', 'TL  ', 'ST  ', 'WT  ', 'PC  '
             '+VC ', '+TL ', '+ST ', '+WT ', '+PC '
  AVTP.......Position tape to desired file:
             'REWI', 'EOT ', 'AVFI'
  BAKLD......Read all files of a catalog entry from BAKTP tape:
             'LOAD', 'PRNT'
  BAKTP......Write all files of a catalog entry to tape in host
             format: 'BACK', 'INIT'
  BLANK......Blank out selected portions of an image:
             'TVCU', 'FIXW', 'FLTW', 'MOMW', 'FLUW', 'SELC',
             'IN2C'
  CCMOD......Generate clean components to fit a model:
             'DISK', 'GAUS'
  CLCAL......Merge & smooth SN tables, apply to CL tables:
             'MERG', 'CALI', 'SMOO:
  CLCOR......Apply corrections to the calibration CL table
             'POLR', 'PHAS', 'OPAC', 'ADEL', 'GAIN', 'CLOC',
             'PANG', 'PONT', 'IONS'
  COMB.......Combine two images:
             'SUM ', 'DIV ', 'SPIX', 'POLI', 'POLA', 'MULT',
             'OPTD', 'CLIP', 'REAL', 'IMAG', 'MEAN', 'RM  ',
             'POLC'
  CONVL......Convolve image with gaussian or another image:
             'GAUS', 'IMAG', 'DGAU'
  CSCOR......Apply specified corrections to CS tables:
             'OPAC', 'GAIN', 'PTRA', 'PTDC'
  DCONV......Deconvolve a gaussian from an image:
             'IN2C', 'UNWT'
  FARAD......Add ionospheric Faraday rotation to CL table:
             'TEC ', 'F0F2', 'MOD '
  FFT........Take Fourier transform of image(s):
             'UVRE', 'UVCX', 'MARE', 'MACX'
  IMMOD......Add images of model objects to an image:
             'GAUS', 'DISK', 'RECT', 'POIN'
  MATHS......Operate on image with choice of math functions:
             'SIN ', 'COS ', 'TAN ', 'ASIN', 'ACOS', 'ATAN',
             'LOG ', 'ALOG', 'LOGN', 'EXP ', 'POLY', 'POWR',
             'MOD '
  MWFLT......Apply linear & non-linear filters to images:
             'MW  ', 'ALFA', 'MODE', 'NRML'
  NINER......Apply various 3x3 area operaters to an image:
             'NINE', 'NORT', 'NE  ', 'EAST', 'SE  ', 'SOUT',
             'SW  ', 'WEST', 'NW  ', 'MSK1', 'MSK2', 'MSK3',
             'SOBL', 'KRSH', 'WALL'
  PATGN......Create a user-specified test pattern:
             'ZONE', 'GAUS', 'LRTZ'
  POLCO......Correct polarization maps for Ricean bias:
             'ZERO', '    '
  QUACK......Flag beginning or end portions of UV-data scans:
             'END ', 'BEG '
  SLCOL......Collate slice data and models:
             'MODL', 'SLVL'
  UVAVG......Average or merge 'BT' or 'TB' sorted UV data:
             'MERG', '    '
  UVDIF......Print differences between two UV data sets:
             'CLIP', 'UVBX', '    '
  UVFIT......Fit gaussian or spheres to UV data:
             'GAUS', 'SPHE'
  UVFLG......Flag selected UV data on disk:
             'FLAG', 'UFLG', 'REAS'
  UVFND......Print UV data selected to search for problems:
             'CLIP', 'FRNG', 'UVBX', 'VCLP'
  UVHGM......Plot statistics (histograms) of uv data files:
             'CLIN', 'CLOG', 'WLIN', 'WLOG'
  UVMOD......Insert a model into uv data:
             'GAUS', 'DISK', 'RECT', 'POIN'
  UVMTH......Correct one uv dataset with the average of another:
             'ADD ', 'SUB ', 'MULT', 'DIV '
  UVSUB......Subtract clean components from a uv data base:
             'DIV ', '    '
  XSMTH......Smooth image data on the x axis only:
             'SMOT', 'INTE'
  XSUM.......Sum or average image data on the x axis only:
             'SUM ', 'AVER'
----------------------------------------------------------------
