Here we provide methods to retrieve rgb triplets, from two huge well-known datasets: the old Unix X11/rgb.txt file and the impressive web-survey carried out by xkcd. There is no bias here between the two (contrary to what happens in matplotlib, which prioritizes X11 names), as you can invoke respectively rgb.X11('colorname') and rgb.xkcd('colorname') to get colors from either the datasets. Both functions share the same API:

1. Both rgb.X11('show') and rgb.xkcd('show') will pop-up an html chart with all colors depicted, in window-based environments. On terminal it will just print all the colornames. Use 'list' instead of 'show' if you want an actual return of the list of colornames (as a cell array).

2. For whatever input other than 'show' and 'list' a powerful string-search engine will scan the selected database and either return the rgb triplet, for exact, case-insentive matches, or provide a list of 'nearest' (in string space!) matches. Try it, you'll find that the 'show' option is quite unuseful at the end of the day. 🙃

   % EXAMPLE
   rgb.xkcd('blue-green')
   Color 'blue-green' not found in xkcd/rgb.
   Consider one of these options:
       {'greenblue' }
       {'bluegreen' }
       {'green/blue'}
       {'blue/green'}
       {'green blue'}
       {'blue green'}

3. Both functions accept not only single characater vectors, but also strings, cells of strings, multiple strings / character vectors. It's as general as possible: whatever valid collection of colornames should work fine.

For more detailed information and examples just invoke the docstrings by typing help rgb.X11, help rgb.xkcd (or use the doc command instead of help for a nicer pop-up window).

© 2014 Chad Greene, original rgb function
© 2022 Gabriele Bellomia, X11 colorset addition All rights reserved.

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