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;

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‘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…
@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.
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