This page was created by the IDL library routine `mk_html_help2`.

Last modified: Fri Nov 7 18:17:52 2025.

# Directory Listing of Routines

# general/misc/system/CSV_Color_Tables

- GET_QUALCOLORS
  Returns a copy of the qualcolors structure.
- LOADCSV
  This is a wrapper/translator for loadcsvcolorbar that loads a CSV color table.
- LOADCSVCOLORBAR2

# Routine Descriptions

## GET_QUALCOLORS

[Next Routine] [List of Routines]

    FUNCTION:   get_qualcolors
    PURPOSE:
      Returns a copy of the qualcolors structure.

    USAGE:
      qualcolors = get_qualcolors()

    INPUTS:
           none

    KEYWORDS:
           none

     $LastChangedBy: dmitchell $
     $LastChangedDate: 2022-07-27 13:38:31 -0700 (Wed, 27 Jul 2022) $
     $LastChangedRevision: 30971 $
     $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/misc/system/CSV_Color_Tables/get_qualcolors.pro $

(See general/misc/system/CSV_Color_Tables/get_qualcolors.pro)

## LOADCSV

[Previous Routine] [Next Routine] [List of Routines]

    PROCEDURE:   loadcsv
    PURPOSE:
      This is a wrapper/translator for loadcsvcolorbar that loads a CSV color table.
      It works the same way that 'loadct2' does.  Restrictions are imposed that make
      this routine compatible with tplot:

        (1) Only eight fixed colors are allowed.  These are loaded into the first
            seven color indices plus the last, with black = 0 and white = 255 (same
            as loadct2).  Missing are the gray25, gray50, gray75, brown, and pink.
            With this change, it is not necessary to manage the top and bottom
            colors.  Use 'get_qualcolors' to access the fixed color names and indices.

        (2) To distinguish the CSV tables from the traditional loadct2 tables, 1000
            is added to the CSV table number.  So 78 becomes 1078, etc.  When tplot
            sees a color table >= 1000, it knows it's a CSV table and uses this
            routine instead of loadct2.

        (3) Only table numbers are allowed.  See qualcolors documentation to find
            out how to define a new table.

        (4) The qualcolors structure is now initialized by this routine and stored
            in a common block, which 'loadcsvcolorbar2' uses.  The stand-alone config
            file 'qualcolors' is ignored, so changes there will have no effect.
            You can get a copy of the qualcolors structure with 'get_qualcolors'.

        (5) !p.color and !p.background are no longer set by default, so you'll have
            to do this yourself (typically in your idl_startup).  See 'revvid', which
            swaps the values for !p.color and !p.background.

      Using 'loadcsv' has the following advantages:

        (1) No need to manage qualcolors, paths, or system variables.  You simply
            use 'loadcsv' the same way you use 'loadct2'.

        (2) 'loadcsv' and 'loadct2' are aware of each other, so both can be used in
            the same session whenever you like, and tplot does not get confused.

        (3) The 'tplot' interface is greatly simplified.  No need to manage the top
            and bottom colors when switching between CSV tables and the standard
            tplot tables.  Color tables can be specified on a panel-by-panel basis,
            with standard tables interspersed with CSV tables:

              options, varname, 'color_table', N
              options, varname, 'reverse_color_table', {0|1}

            with N < 1000 for standard tables and N >= 1000 for CSV tables.  As usual,
            varname can be an array of tplot variable names or indices to affect
            multiple panels with one command.  Variable names can contain wildcards
            for the same purpose.

      If you are already using the original qualcolors and 'loadcsvcolortable', and
      you're happy with how that works, you can keep doing things that way.  This
      routine will not interfere.

    USAGE:
      loadcsv, colortbl [, KEYWORD=value, ...]

    INPUTS:
           colortbl:     CSV table number + 1000.  Don't forget to add 1000!
                         If this input is missing, then keyword CATALOG is set.

    KEYWORDS:
           RESET:        Reset the qualcolors structure with the default fixed
                         line colors, then load colortbl.

           PREVIOUS_CT:  Named variable to hold the previous color table number.
                         Tplot needs this to swap color tables on the fly.

           PREVIOUS_REV: Named variable to hold the previous color reverse.
                         Tplot needs this to swap color tables on the fly.

           CATALOG:      Display an image of the CSV color tables and return.
                         Does not load a color table.

           LINE_CLRS:    Defines custom line colors.  Can take one of two forms:

                         Array of 24 (3x8) RGB values that define 8 fixed colors
                         (the first 7 and the last) of the color table:
                           LINE_CLRS = [[R,G,B], [R,G,B], ...].

                         Integer from 0 to 10 that selects one of the predefined sets
                         of fixed line colors.  Except for primary colors, these
                         are suitable for colorblind vision.

                           0  : primary colors
                          1-4 : four different schemes suitable for colorblind vision
                           5  : primary colors, except orange replaces yellow for better contrast on white
                           6  : primary colors, except gray replaces yellow for better contrast on white
                           7  : see https://www.nature.com/articles/nmeth.1618 except no reddish purple
                           8  : see https://www.nature.com/articles/nmeth.1618 except no yellow
                           9  : same as 8 but permuted so vector defaults are blue, orange, reddish purple
                          10  : Chaffin's CSV line colors, suitable for colorblind vision

                         Default = 10.

           LINE_COLOR_NAMES:  String array of 8 line color names.  You must use line color
                         names recognized by spd_get_color().  RGB values for unrecognized
                         color names are set to zero.  Not recommended, because named
                         colors are approximated by the nearest RGB neighbors in the
                         currently loaded color table.  This can work OK for rainbow color
                         tables, but for tables that primarily encode intensity, the
                         actual colors can be quite different from the requested ones.
                         Included for backward compatibility.

           COLOR_NAMES:  Synonym for LINE_COLOR_NAMES.  Allows better keyword minimum
                         matching.  Both keywords are accepted - this one takes precedence.

           MYCOLORS:     A structure defining up to 8 custom colors.  These are
                         fixed colors used to draw colored lines (1-6) and to define
                         the background (0) and foreground (255) colors.

                         { ind    : up to 8 integers (0-6 or 255)              , $
                           rgb    : up to 8 RGB levels [[R,G,B], [R,G,B], ...]    }

                         The indicies (ind) specified in MYCOLORS will replace one or
                         more of the default colors.  You are not allowed to change
                         color indices 7-254, because those are reserved for the
                         color table.  Indices 0 and 255 allow you to define custom
                         background and foreground colors.

                         Changes made with LINE_CLRS and MYCOLORS are persistent, so
                         you can change the color table (indices 7-254) while keeping
                         the same fixed line colors.  Use line_colors.pro to do the
                         reverse: change the line colors while keeping the color table.

           GRAYBKG:      Set color index 255 to gray [211,211,211] instead of white.
                         See keyword MYCOLORS for a general method of setting any line
                         color to any RGB value.  For example, GRAYBKG=1 is equivalent
                         to MYCOLORS={ind:255, rgb:[211,211,211]}.

                         To actually use this color for the background, you must set
                         !p.background=255 (normally combined with !p.color=0).

           Also passes all keywords accepted by loadcsvcolorbar2.

    See also:
       "initct","line_colors","get_line_colors","loadcsv","get_colors","colors_com","bytescale"

     $LastChangedBy: dmitchell $
     $LastChangedDate: 2023-03-05 09:49:05 -0800 (Sun, 05 Mar 2023) $
     $LastChangedRevision: 31584 $
     $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/misc/system/CSV_Color_Tables/loadcsv.pro $

    CSV color table code: Mike Chaffin
    Tplot-compatible version: David L. Mitchell

(See general/misc/system/CSV_Color_Tables/loadcsv.pro)

## LOADCSVCOLORBAR2

[Previous Routine] [List of Routines]

    ; PROCEDURE LOADCSVCOLORBAR2.PRO
    ; commands to load a CSV color table file from a local directory,
    ; along with some colorbrewer qualitative colors in selected indices,
    ; as defined in qualcolors file
    ;
    ; This version is modified to be compatible with tplot.  It is no
    ; longer intended to be called directly.  Use loadcsv instead.
    ;
    ; OPTIONAL:
    ;
    ; COLORTBL: the CSV file basename (no directory or extension) or
    ; index of the colorbar to load. This must refer to a three column
    ; CSV file with RGB values of the colors to load into the color
    ; table. Interpolation will be performed over the color entries to
    ; fit the color table into the available space. If omitted, the user
    ; can interactively select from the available colorbars via a dialog.
    ;
    ; DIRECTORY=: overrides the default search directory with a user
    ; specified directory.
    ;
    ; /SILENT: when loading a color table by index, by default the name
    ; of the color table is printed. With this flag set, no output is
    ; printed.
    ;
    ; /REVERSE: load the color table so that the color indices in IDL are
    ; reversed relative to the order in the file.
    ;
    ; /NOQUAL: load the color table without the qualitative colorbrewer
    ; colors. Unless the color table contains them at the ends of the
    ; range, white and black will not be accessible with this flag
    ; enabled.
    ;
    ; RGB_TABLE=: return 3x256 array of the RGB values loaded into the
    ; current color table.
    ;
    ; LOW_QUANT=: load only the file indices above the specified quantile
    ; into the color table (e.g. to load only the upper half of the
    ; colors in the file specify LOW_QUANT=0.5)
    ;
    ; HIGH_QUANT=: load only the file indices below the specified quantile
    ; into the color table (e.g. to load only the lower half of the
    ; colors in the file specify HIGH_QUANT=0.5)
    ;
    ; WHITEBACK=: sets !p.color = black, !p.background = white
    ;
    ; BLACKBACK=: sets !p.color = white, !p.background = black
    ;

     Created by M. Chaffin
     Modified by D. Mitchell for compatibility with tplot

     $LastChangedBy: dmitchell $
     $LastChangedDate: 2022-07-20 13:13:54 -0700 (Wed, 20 Jul 2022) $
     $LastChangedRevision: 30950 $
     $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/misc/system/CSV_Color_Tables/loadcsvcolorbar2.pro $

(See general/misc/system/CSV_Color_Tables/loadcsvcolorbar2.pro)