; UV4TYPE
;---------------------------------------------------------------
;! Convolving function type 4, exponent times sinc function
;# INFORMATION UV
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UV4TYPE   LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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UV4TYPE
Type: information only.
Information:  Convolving function type 4 = Exp * Sinc
      Function = SINC ( ABS(U) / PARM(2) ) *
                    EXP ( - ((ABS(U)/PARM(3)) ** PARM(4)) )

      Parameters are:
         PARM(1) = Support size.  0 --> 3.0 cells
         0 --> PARM(2) = 1.55 cells
         0 --> PARM(3) = 2.52 cells
         0 --> PARM(4) = 2.0
      See memos by Fred Schwab for more details; large support size
      may have undesired results. Changing these can put divides by
      zero in the map plane and can reduce the degree of alias
      suppression.  See the VLA Scientific Memo Series 123, 124, 129,
      and 131.  See also Synthesis Imaging in Radio Astronomy, ASP
      Conference Series, Volume 6, pages 130-134.

      Types 4 and -4 are rectilinear (in X and Y separately), types 14
      and -14 are circular (in R = sqrt(X*X+Y*Y)).

      Types -4 and -14 are for single-dish use and have units of arc
      seconds for PARM(1) with default = single-dish-beam_size and for
      PARM(2) with default =  1.55 * single-dish-beam_size/3 and for
      PARM(3) with default =  2.52 * single-dish-beam_size/3.

Tasks:
HORUS....Interferometer imaging with calibration, no Cleaning.
IMAGR....Interferometer imaging with calibration, Cleaning, and
         wide-field corrections.
MX.......Interferometer imaging with Cleaning, no calibration.
SCMAP....Interferometer imaging with Cleaning, self-calibration and
         interactive editing.
UVMAP....Interferometer imaging with no Cleaning, no calibration.
WFCLN....Interferometer imaging with Cleaning and wide-field
         corrections, but no calibration.

COMPL....Plot aspects of the convolving functions.

BSGEO....Single-dish re-grid from pseudo az-el to RA-dec.
BSGRD....Single-dish continuum beam-switched imaging and correction.
SDIMG....Single-dish imaging able to do large fields (with large scratch
         files).
SDGRD....Single-dish imaging.
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