Path: news.mathworks.com!not-for-mail From: <HIDDEN> Newsgroups: comp.soft-sys.matlab Subject: Re: sorry for this question, maybe is not the right place here? Date: Sun, 3 Apr 2011 20:45:05 +0000 (UTC) Organization: The MathWorks, Inc. Lines: 25 Message-ID: <inam8h$6u2$1@fred.mathworks.com> References: <inafio$reg$1@fred.mathworks.com> <inak7b$73g$1@fred.mathworks.com> Reply-To: <HIDDEN> NNTP-Posting-Host: www-00-blr.mathworks.com Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Trace: fred.mathworks.com 1301863505 7106 172.30.248.45 (3 Apr 2011 20:45:05 GMT) X-Complaints-To: news@mathworks.com NNTP-Posting-Date: Sun, 3 Apr 2011 20:45:05 +0000 (UTC) X-Newsreader: MATLAB Central Newsreader 1187260 Xref: news.mathworks.com comp.soft-sys.matlab:719815 "Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <inak7b$73g$1@fred.mathworks.com>... > "Sofia HĂ¤ggberg" wrote in message <inafio$reg$1@fred.mathworks.com>... > > what is the difference between hamming and euclidian distance? I think they're quite similar right... > > No, They aren't. > > Hamming is l1-distance: sum | ai - bi | > Euclidian is l2-distance [ sum | ai - bi |^2 ] ^ (1/2) > > In general lp-distance is defined as > [ sum | ai - bi |^p ] ^ (1/p), where 1 <= p < inf > > The limit of lp is called l_infinity and it can be showed as > linf = max_i | ai - bi | > > Bruno - - - - - - - - - - I think the Hamming distance is actually an l0 (letter "l") "norm", though it is not really a proper norm. See http://en.wikipedia.org/wiki/Lp_space http://en.wikipedia.org/wiki/Hamming_distance Roger Stafford