; AXVAL
;---------------------------------------------------------------
;! Value of axis coordinate at reference pixel
;# ADVERB CATALOG
;-----------------------------------------------------------------------
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;---------------------------------------------------------------
AXVAL     LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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AXVAL
Type: Adverb    (array(2))
Use:  To specify the value of the coordinate at the reference pixel on a
      specified axis.  FITS standard units are mks with degrees and Jy
      added.  AXVAL is an array to allow greater precision in the
      specified value.  The axis value is taken to be AXVAL(1) +
      AXVAL(2) with both values converted to double precision before
      adding.  For example, the frequency 1.420405752E6 is too precise
      for a single adverb.  However, AXVAL = 1.4204E6, 5752. will
      convey the desired value correctly.  NOTE, if AXVAL(1) = AXVAL(2),
      then the axis value is taken to be just AXVAL(1).
Null value: none
Verbs:
   ALTDEF........Sets frequency vs velocity relationship into image
                 header.  AXVAL is the reference pixel velocity in
                 meters/sec.
   AXDEFINE......Define or modify an image axis description.
                 AXVAL must be specified.
Tasks:
   PLAYR.........Task to load one or two images and play with them on the
                 TV.  AXVAL is used as the intensity display range for
                 the second input image (if any).
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