; NFIELD
;---------------------------------------------------------------
;! The number of fields imaged
;# ADVERB IMAGING
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
NFIELD    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
NFIELD
Type: Adverb   (Real)
Use:  The number of fields associated with a verb, task, or adverb.
      Up to 64 are allowed in normal imaging tasks without use of a
      BOXFILE.  IMAGR has a limit of 4096 with a BOXFILE.

      NFIELD is normally not used in the presence of a BOXFILE.
Null value:  0
      Null value is usually assigned 1.
Tasks:
   BOXES.......Adds Clean boxes to BOXFILE around sources from a list.
   CHKFC.......Makes images of Clean boxes from Boxfile.
   FILIT.......Interactive BOXFILE editing with facet images.
   FIXBX.......Converts a BOXFILE to another for input to IMAGR.
   FLATN.......Re-grid multiple fields into one image incl sensitivity.
               NFIELD is the maximum number of facets per pointing.
   IMAGR.......Wide-field and/or wide-frequency Cleaning / imaging task.
   SABOX.......Create box file from source islands in facet images.
   SCIMG.......Full-featured imaging plus self-calibration loop with
               editing.
   SETFC.......Makes a BOXFILE for input to IMAGR.  NFIELD is an output
               adverb.
Verbs:
   DFILEBOX....Verb to delete Clean boxes with TV cursor & write to
               file.
   DRAWBOX.....Verb to draw Clean boxes on the display.  NFIELD is the
               facet number to attach to the boxes.
   FILEBOX.....Verb to reset Clean boxes with TV cursor & write to file.
               NFIELD is the facet number to attach to the boxes.
Procedures:
   LINIMAGE....Build image cube from multi-IF data set.  FLDSIZE passed
               to IMAGR.
   MAPPR.......Simplified access to IMAGR.
   PEELR.......Calibrates interfering sources in multi-facet imges.
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