I don't know if this has already been addressed here, but I just found this issue when I experimented a bit with ODEs in Xcas and the HP-Prime.
There's an inconsistency between the 'Home' and CAS mode:
in Home mode vector/list elements are counted starting with 1 (which is the usual way in math), but in CAS mode (and Xcas itself) the indices start with 0. :-(
Argh, that's really terrible and absolutely unusual (and unacceptable) in mathematics. I know that starting array indexing with 0 is usual practice in some programming languages, but NOT in math, and I can't believe that someone could come up with this idea.
In [a,b,c] there's a 1st, 2nd and 3rd element, but definitely no 'element 0'!
Franz
Edited: 27 Oct 2013, 2:56 p.m.