; NCHAV
;---------------------------------------------------------------
;! Number of channels averaged in an operation
;# ADVERB SPECTRAL
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
NCHAV     LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
NCHAV
Type: Adverb   (scalar)
Use:  To specify the number of channels (usually spectral channels) to
      be "averaged" together in some operation.  Note that imaging
      programs "average" channels by gridding them separately into the
      same output image using the u,v,w's corrected for each channel
      frequency.
Null value:  0 -> 1
Tasks:
  DFTIM......Makes image of DFT at arbitrary point showing time vs
             frequency.
  IMAGR......Converts visibility data into images, performing
             deconvolutions as desired.  NCHAV specifies the number of
             spectral channels contributing to each output image.
  PLOTC......Plots color schemes used by 3-color plot tasks.
  SPLIT......Applies calibration and flagging to multi-source
             visibility data, producing single-source data files.
             NCHAV is the number of input spectral channels averaged
             (in the usual sense) into each output spectral channel.
  TVFLG......Interactive flagging of UV data using the TV.
  UFLAG......Plots and edits data using a uv-plane grid and the TV.
  UVFND......Prints selected data from UV data set to search for
             problems.
  UVIMG......Grid UV data into an "image".
  UVPLT......Plots data from a UV data base in multiple ways.
  WIPER......Plots and edits data from a UV data base using the TV.
"Verbs"
  OBITIMAG...Access to OBIT task Imager without self-cal or peeling.
  OBITMAP....Simplified access to OBIT task Imager,
  OBITPEEL...Access to OBIT task Imager with self-cal and peeling.
  OBITSCAL...Access to OBIT task Imager with self-cal, NOT peeling.
  SIZEFILE...Return file size plus estimate of IMAGR work file size.
Procedures:
  LINIMAGE...Build image cube from multi-IF data set.
  MAPPR......Simplified access to IMAGR.
----------------------------------------------------------------
