; PIXXY
;---------------------------------------------------------------
;! Specifies a pixel location.
;# ADVERB IMAGING
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
PIXXY     LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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PIXXY
Type: Adverb (Real*7)
Use:  Specifies a pixel position in an image.  The first number gives
      the column number and the second number gives the row number.  The
      (1,1) pixel location is the bottom left corner of the image.
      Fractional pixel values can be used.

      With tables PIXXY(1) is the row, PIXXY(2) is the column, and
      PIXXY(3) is the subscript.
Null value:  0
       Null value often means at reference pixel but in many cases the
       mull value is an error.
Verbs:
   COPIXEL.......Convert between physical and pixel coordinate values.
   IM2TV.........Verb to convert pixel coordinates to TV pixels.
   IMCENTER......Returns pixel position of sub-image centroid.
   IMDIST........Determines spherical distance between two pixels.
                 PIXXY is the pixel position in the first image.
   IMSTAT........Returns statistics of a sub-image.  PIXXY is the
                 coordinate of the peak value in the window.
   IMVAL.........Returns image intensity and coordinate at specified
                 pixel.
   IMXY..........Returns pixel coordinates selected by the TV cursor.
   MAXFIT........Returns pixel position and image intensity at a maximum.
                 PIXXY is the pixel coordinates of the fit peak.
   PUTVALUE......Verb to store a pixel value at specified position.
   QIMVAL........Returns image intensity and coordinate at specified
                 pixel.
   TABGET........Returns table entry for specified row, column and
                 subscript.  PIXXY has the table usage.
   TABPUT........Replaces table entry for specified row, column and
                 subscript.  PIXXY has the table usage.
   TKXY..........Verb to obtain pixel value under cursor.
   TVILINE.......Verb to draw a straight line on an image on the TV.
                 PIXXY is the position of the start point of the line.
   TVSTAT........Find the mean and RMS in a blotch region on the TV.
                 PIXXY is the coordinate of the peak value in the blotch.
Procedures:
   SETXWIN.......Procedure to set BLC and TRC with TV cursor.  PIXXY is
                 the center of the selected subimage.
   TKBOX.........Procedure to set a Clean box with the TK cursor.
                 PIXXY is the TRC of the box.
   TKNBOXS.......Procedure to set Clean boxes 1 - n with the TK cursor.
                 PIXXY is the TRC of box n.
   TKWIN.........Procedure to set BLC and TRC with Graphics cursor.
                 PIXXY is the TRC of the window.
   TVDIST........Determines spherical distance between two pixels on TV
                 screen.  PIXXY is the pixel location of the first point.
   TVFLUX........Displays coordinates and values selected with the TV
                 cursor.  PIXXY is the pixel location of the last
                 selected point.
   TVMAXFIT......Displays fit pixel positions and intensity at maxima on
                 TV.
Tasks:
   CCMOD.........Generates clean components to fit specified source model.
                 PIXXY is the center of the model.
   PASTE.........Pastes a selected subimage of one image into another.
                 PIXXY is the pixel in the first image to be aligned with
                 the selected point in the second image.
   SLCOL.........Task to collate slice data and models.  PIXXY is the
                 reference point from which distances are computed.
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