Path: news.mathworks.com!not-for-mail From: <HIDDEN> Newsgroups: comp.soft-sys.matlab Subject: Re: expectated value Date: Tue, 15 Jan 2013 15:10:08 +0000 (UTC) Organization: The MathWorks, Inc. Lines: 35 Message-ID: <kd3rgg$d1h$1@newscl01ah.mathworks.com> References: <kd31i0$ckc$1@newscl01ah.mathworks.com> <kd34i6$p21$1@speranza.aioe.org> <kd3p99$3qu$1@newscl01ah.mathworks.com> Reply-To: <HIDDEN> NNTP-Posting-Host: www-05-blr.mathworks.com Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Trace: newscl01ah.mathworks.com 1358262608 13361 172.30.248.37 (15 Jan 2013 15:10:08 GMT) X-Complaints-To: news@mathworks.com NNTP-Posting-Date: Tue, 15 Jan 2013 15:10:08 +0000 (UTC) X-Newsreader: MATLAB Central Newsreader 3799640 Xref: news.mathworks.com comp.soft-sys.matlab:786596 "maryam" wrote in message <kd3p99$3qu$1@newscl01ah.mathworks.com>... > "Nasser M. Abbasi" wrote in message <kd34i6$p21$1@speranza.aioe.org>... > > On 01/15/2013 01:47 AM, maryam wrote: > > > Dear friens > > > I would like calculate the expectated value (E(.)) of a 1-by-1000 matrix > > > {E(x)=sigma x*f(x)} > > > how do I that? > > > > Apply the definition of expected value? > > > > when you are not sure how to do something, always look up > > the definition and go from there. > > > > http://en.wikipedia.org/wiki/Expected_value > > > > If you have problem with implementing the defintion, then show > > what you tried and where you are having problem. > > > > good luck, > > > > --Nasser > -------------------- > I know the the definition of expected value but I cant implement it. > assume a 1-by-n arbitrary matrix, what's its matlab code? > thanks A row of numbers does not have an expected value. What you probably mean is an estimator for the expected value of the random variable which produced the row of numbers. Usually one takes mean(A,2) for this where A is your 1xn - matrix. Best wishes Torsten.