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      Build and/or Edit an absolute color table.


Calling Sequence



Keyword Parameters


Common Blocks


      Notes: An absolute color table is used to map data
      values to specified colors, always the same color for the
      same value. A color table is built by defining colors at
      specified points called tiepoints. The table starts
      with two tiepoints, the start and end. Each tiepoint
      has a value entry area and a color patch. The value may
      be changed to move the tiepoint. The color may be changed
      by clicking on the color patch and using the color picker
      to change the color. Tiepoints may be added or dropped.
      Colors between tiepoints are interpolated, either in RGB
      color space, or HSV color space. The table may also be
      stepped into descrete color steps of a specified size.
      The color table may be saved in a text file and read
      back in. The tiepoints LO and HI are the table endpoints
      and define the range of the table. The range may be
      changed by changing the values of these points. The Bar
      min and max just set how much of the table is displayed,
      not the actual range covered by the table. When the table
      is applied to data using act_apply then data is clipped to
      the range of the table (which may be freely changed in that
      routine). The tiepoints positions are displayed above the
      color bar.
      To apply a color table to data:
        img = act_apply(data,file=color_table)
        (see the built-in help for more options).
      To display a color bar:
          act_cbar, vmin, vmax
        (see the built-in help for more options).

Modification History

      R. Sterner, 2007 Dec 17
      R. Sterner, 2007 Dec 30 --- Fixed some minor problems.
                                  Tried wheel events.
      R. Sterner, 2008 Jan 08 --- Added a 2nd color picker option.
      R. Sterner, 2008 May 21 --- Saved and read barmin, barmax.
      R. Sterner, 2009 Mar 10 --- Now uses dialog_pickfile to open a file.
      R. Sterner, 2010 Mar 22 --- Allowed extra items in file.
      R. Sterner, 2010 Apr 08 --- Minor cleanup.
      R. Sterner, 2010 Apr 12 --- Fixed problem writing out act_x.
      R. Sterner, 2010 Nov 15 --- Added log flag. Log tables not yet ready.
      R. Sterner, 2010 Nov 29 --- Making log color table work.
      R. Sterner, 2010 Nov 29 --- Also adjusted tiepoint Y scroll size,
                                  added file name.
      R. Sterner, 2010 Nov 30 --- Rearranged layout a bit. Animated text input.
      R. Sterner, 2010 Dec 01 --- Minor tweaks.
      R. Sterner, 2010 Dec 30 --- Handled units conversion.
      R. Sterner, 2010 Dec 31 --- Increased save file name entry area.
      R. Sterner, 2011 Jan 02 --- Included act_edit_ucon_d internally.
  Copyright (C) 2007, Johns Hopkins University/Applied Physics Laboratory
  This software may be used, copied, or redistributed as long as it is not
  sold and this copyright notice is reproduced on each copy made. This
  routine is provided as is without any express or implied warranties
  whatsoever. Other limitations apply as described in the file disclaimer.txt.

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