Undocumented Matlab
  • SERVICES
    • Consulting
    • Development
    • Training
    • Gallery
    • Testimonials
  • PRODUCTS
    • IQML: IQFeed-Matlab connector
    • IB-Matlab: InteractiveBrokers-Matlab connector
    • EODML: EODHistoricalData-Matlab connector
    • Webinars
  • BOOKS
    • Secrets of MATLAB-Java Programming
    • Accelerating MATLAB Performance
    • MATLAB Succinctly
  • ARTICLES
  • ABOUT
    • Policies
  • CONTACT
  • SERVICES
    • Consulting
    • Development
    • Training
    • Gallery
    • Testimonials
  • PRODUCTS
    • IQML: IQFeed-Matlab connector
    • IB-Matlab: InteractiveBrokers-Matlab connector
    • EODML: EODHistoricalData-Matlab connector
    • Webinars
  • BOOKS
    • Secrets of MATLAB-Java Programming
    • Accelerating MATLAB Performance
    • MATLAB Succinctly
  • ARTICLES
  • ABOUT
    • Policies
  • CONTACT

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
Print Print
« Previous
Next »
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 […]

Leave a Reply
HTML tags such as <b> or <i> are accepted.
Wrap code fragments inside <pre lang="matlab"> tags, like this:
<pre lang="matlab">
a = magic(3);
disp(sum(a))
</pre>
I reserve the right to edit/delete comments (read the site policies).
Not all comments will be answered. You can always email me (altmany at gmail) for private consulting.

Click here to cancel reply.

Useful links
  •  Email Yair Altman
  •  Subscribe to new posts (email)
  •  Subscribe to new posts (feed)
  •  Subscribe to new posts (reader)
  •  Subscribe to comments (feed)
 
Accelerating MATLAB Performance book
Recent Posts

Speeding-up builtin Matlab functions – part 3

Improving graphics interactivity

Interesting Matlab puzzle – analysis

Interesting Matlab puzzle

Undocumented plot marker types

Matlab toolstrip – part 9 (popup figures)

Matlab toolstrip – part 8 (galleries)

Matlab toolstrip – part 7 (selection controls)

Matlab toolstrip – part 6 (complex controls)

Matlab toolstrip – part 5 (icons)

Matlab toolstrip – part 4 (control customization)

Reverting axes controls in figure toolbar

Matlab toolstrip – part 3 (basic customization)

Matlab toolstrip – part 2 (ToolGroup App)

Matlab toolstrip – part 1

Categories
  • Desktop (45)
  • Figure window (59)
  • Guest bloggers (65)
  • GUI (165)
  • Handle graphics (84)
  • Hidden property (42)
  • Icons (15)
  • Java (174)
  • Listeners (22)
  • Memory (16)
  • Mex (13)
  • Presumed future risk (394)
    • High risk of breaking in future versions (100)
    • Low risk of breaking in future versions (160)
    • Medium risk of breaking in future versions (136)
  • Public presentation (6)
  • Semi-documented feature (10)
  • Semi-documented function (35)
  • Stock Matlab function (140)
  • Toolbox (10)
  • UI controls (52)
  • Uncategorized (13)
  • Undocumented feature (217)
  • Undocumented function (37)
Tags
ActiveX (6) AppDesigner (9) Callbacks (31) Compiler (10) Desktop (38) Donn Shull (10) Editor (8) Figure (19) FindJObj (27) GUI (141) GUIDE (8) Handle graphics (78) HG2 (34) Hidden property (51) HTML (26) Icons (9) Internal component (39) Java (178) JavaFrame (20) JIDE (19) JMI (8) Listener (17) Malcolm Lidierth (8) MCOS (11) Memory (13) Menubar (9) Mex (14) Optical illusion (11) Performance (78) Profiler (9) Pure Matlab (187) schema (7) schema.class (8) schema.prop (18) Semi-documented feature (6) Semi-documented function (33) Toolbar (14) Toolstrip (13) uicontrol (37) uifigure (8) UIInspect (12) uitools (20) Undocumented feature (187) Undocumented function (37) Undocumented property (20)
Recent Comments
  • Iñigo (2 days 3 hours ago): Thanks Yair. I didn’t realize it was posted just above. It would be great to know about a solution soon
  • Yair Altman (3 days 10 hours ago): @Iñigo – your query is related to Seth’s question above. We can access the currently-browsed URL in JavaScript (for example: jBrowserPanel.executeScript...
  • Iñigo (5 days 2 hours ago): I am looking for setting a UI that allows following process: opening a web site, navigate inside this web site and at some specific moments (i.e. when the figure is closed or a button...
  • Nicholas (12 days 8 hours ago): Yair, this works wonderfully! I can’t thank you enough!
  • Collin (14 days 11 hours ago): Seth Good point, I am using 2022b, mathworks seems to have started using CEF browsers from 2019a, best I can tell. take a look at the package com.mathworks.toolbox.matla...
  • Seth (15 days 4 hours ago): Collin, What version of MATLAB are you using?
  • Collin (20 days 10 hours ago): Seth, I have had some success executing javascript that requires no return value by executing it directly (sort of) on the org.cef.browser.CefBrowser that a...
  • Coo Coo (22 days 5 hours ago): FFT-based convolution is circular whereas MATLAB’s conv functions have several options (‘valid’, ‘same’, ‘full’) but unfortunately not...
  • Seth (22 days 8 hours ago): No luck with removing the space.
  • Seth (22 days 9 hours ago): The javascript code works fine running the application from the 2019b desktop version and the 2016b deployed version.
  • Seth (22 days 10 hours ago): I have been using this browser functionality in 2016b because it works fully in deployed applications in that version. However, because of Java 7 being flagged as a security risk, I...
  • Yair Altman (22 days 10 hours ago): I’ve never tested javascript callbacks, but perhaps you should try removing the extra space after the “matlab:” protocol specifier. Does it make any difference?
  • Seth (22 days 10 hours ago): I have been using this functionality in 2016b since it works in deployed applications and have not had a reason to need to upgrade but with java 7 being flagged as a security risk I am...
  • KEVIN (42 days 11 hours ago): I apologize, I intended my response to fall under ‘T’ but did not seem to work. I was referring to the bit of code posted by ‘T’ regarding the toolgroup and...
  • Yair Altman (42 days 11 hours ago): It is not clear from your comment which code exactly you are referring to and what you see differently in 19b vs. 20b, so I cannot assist with your specific query. In general I...
Contact us
Undocumented Matlab © 2009 - Yair Altman
This website and Octahedron Ltd. are not affiliated with The MathWorks Inc.; MATLAB® is a registered trademark of The MathWorks Inc.
Scroll to top