there is a uppvparse related compiler bug fix report 452577 (release 2008b) in
I tried the sunspot.dat initial lines and work fine in R2015.
There are 4 findpeaks related bugs 650368(2010b), 582260(2010a), 452577(2008b) same as above, and 489930(2009a).
I have also tried the code you added later on and no problem in 2015.
If I were you, if not out of experience, just for the cost of a student licence, it really pays off to save a few pizzas and beer, and get MATLAB updated, really.
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