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Spy Easter egg

April 11, 2009 4 Comments

For the 2009 Easter holiday, I thought I’d post a Matlab Easter egg, which I found on http://www.eeggs.com/items/47352.html: spy is a built-in stock Matlab function for visualizing sparse matrices. If you run spy with no input arguments, it uses an undocumented default built-in sparse matrix that generates one of the spies in the famous Spy vs. Spy comics series:

spy;

spy;

Matlab spy Easter egg

Related posts:

  1. Spy Easter egg take 2 – The default spy Easter-egg image in the spy function has recently changed. ...
  2. Image Easter egg – The default image presented by Matlab's image function has a very interesting undocumented story....
  3. Undocumented scatter plot behavior – The scatter plot function has an undocumented behavior when plotting more than 100 points: it returns a single unified patch object handle, rather than a patch handle for each specific point as it returns with 100 or less points....
  4. Performance: scatter vs. line – In many circumstances, the line function can generate visually-identical plots as the scatter function, much faster...
  5. Using Infiniband with Matlab Parallel Computing Toolbox – Infiniband networking can significantly improve PCT performance in Matlab parallelization and distributed computing. ...
  6. Bar plot customizations – Matlab bar charts can be customized in various nifty ways. ...
Easter egg Pure Matlab spy Undocumented feature
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4 Responses
  1. Naor April 12, 2009 at 15:46 Reply

    ‘spy’ with no arguments was one of the first MATLAB commands I learned 🙂
    another one was ‘why’ with no arguments, maybe you consider that an Easter egg as well…

    • Yair Altman April 12, 2009 at 23:08 Reply

      @Naor – the difference is that why with no args is documented, so it’s fun but not a real Easter egg.
      Spy with no args is not documented.

  2. Image Easter egg | Undocumented Matlab April 6, 2010 at 10:28 Reply

    […] Last year I presented the Matlab Spy Easter egg for the 2009 Easter holiday. This year, slightly late, I present another Easter egg […]

  3. Spy Easter egg take 2 | Undocumented Matlab April 5, 2012 at 00:36 Reply

    […] Three years ago, I posted a short post about Matlab’s built-in Easter egg in the spy function […]

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