I tryed all the time other functions... but now! ;-)

I do not reach this... :-/

new comment here: http://www.mathworks.com/matlabcentral/cody/solutions/470839#comment_4173

No they did not. I believe then this did not work because @char/regexp takes precedence over your regexp function... this will work if you use instead another among the "three" (this is a hint) functions called by the testsuite before the error occurs (this happens when evaluating "tf{1}")...

I tryed also this:
http://www.mathworks.com/matlabcentral/cody/problems/537-cody-computer-part-3-detect-the-graphic-card-used-on-cody-computer/solutions/470848

but it also does not work. :-(

Ha, I followed the same sequence. Third time (and third function to overload) is a charm. Just look at the first test in the testsuite again :)

There must be a problem with the test 1. The displayed error comes from the test case not from my code. If your_fcn_name returns just a string the error will be displayed too!

I am having a similar problem. My code returns an identical match to the test case code when I run it in MATLAB, but I'm receiving an "Index exceeds matrix dimensions" error here.

This ought to be the best solution (size 14)