Maxima vs. other CAS systems



Greetings!  I was just wondering if there was an unbiased analysis out
there somewhere comparing available CAS systems, free and non-free, in
terms of features, robustness, usefulness, etc.  Also, is there a
brief howto available describing how a user might implement missing
functionality in an add-on package -- i.e. how does one integrate into
maxima's rule system?

Take care,


-- 
Camm Maguire			     			camm@enhanced.com
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"The earth is but one country, and mankind its citizens."  --  Baha'u'llah