On Wed, Apr 25, 2007 at 09:10:57AM -0300, Martin Marques wrote: > Please, tell me I haven't lost it yet. > > octave:14> -5^4 > ans = -625 > > Since when does an even power of a negative number give a negative result? > It's precedence has fooled you. ^ has higher procedence than - so what you have calculated is:- - ( 5 ^ 4 ) To get the answer you are expecting you need to type:- (-5)^4 -- Chris Green