Thank's Pedro Madrones, you're right that i have removed my name of the email (because of Spam, and datas that i can't remove on the net). Ok, i explain a bit more :
X is a centred matrix. PCA summarise all variation of X into a few new variables called scores T.These new variables are linearly weighted combinations of the original X-variables. The loadings P contain the weights used for each X variable and thus reveal the influence of individual X-variables. Is it ok ? That's what give the nipals function of chemometrics package. It's just that i don't understand how to use The T and P matrix to have the component matrix. i don't need explainations how to obtain P and T.... But in how to do E = X tp. But maybe it's not there for this kind of questions, i am not from chemometrics science. *** Johannes E. S. 2011/12/5 Pedro Mardones <mardone...@gmail.com> > Perhaps you can try the examples given in > http://www.jstatsoft.org/v18/i02 for getting a better idea about how > the NIPALS algorithm works. BTW, yes,it looks like a homework question > specially when your user name is "zz dd <void1...@gmail.com>" so you > can't be recognized. > > > > On Mon, Dec 5, 2011 at 9:27 AM, zz dd <void1...@gmail.com> wrote: > > Thank you for your brevity you don't have to say more things to show who > > you are. > > Else if you don't understand what we are talking about, you shouldn't be > > rude and insulting. > > May be you are quite young please take time to read Nonaka and Takeuchi > and > > moreover Takanashi to uderstand the way to go from information to > knowledge > > to wisdom that's quite useful for IS / IT and should bring you a bit of > > etiquette. > > *I have a dream* *that one day this nation will rise up and live out the > > true meaning of its creed : We hold these truths to be self-evident : > that > > all men are created equal.* > > > > Have a nice day. > > > > 2011/12/5 Jeff Newmiller <jdnew...@dcn.davis.ca.us> > > > >> This is not a homework help list. > >> > --------------------------------------------------------------------------- > >> Jeff Newmiller The ..... ..... Go > Live... > >> DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live > >> Go... > >> Live: OO#.. Dead: OO#.. Playing > >> Research Engineer (Solar/Batteries O.O#. #.O#. with > >> /Software/Embedded Controllers) .OO#. .OO#. > rocks...1k > >> > --------------------------------------------------------------------------- > >> Sent from my phone. Please excuse my brevity. > >> > >> zz dd <void1...@gmail.com> wrote: > >> > >> >Hello > >> >The solution maybe there but i need to compute it into R if someone can > >> >help me : > >> >(Previously store score vector t in score matrix T; store loading > >> >vector p > >> >in loading matrix P) that's done by nipals in chemometrics > >> >After use of nipals function you have T and P matrix > >> > > >> >First : "Calculate the residual matrix of X. Stop if the elements of > >> >Xres > >> >are very small > >> >because no further PCA components are reasonable" : > >> >Xres= X-u.b(T) > >> > > >> >u : improved score vector > >> >b: loading vector > >> >X : a mean-centered matrix > >> > > >> >Second : Replace X with Xres and continue with step 2 (with nipals > >> >chemometrics...) for calculation of the next PCA > >> >component. > >> > > >> >If someone can help me ? > >> >Thank's a lot > >> > > >> > > >> >2011/12/1 zz dd <void1...@gmail.com> > >> > > >> >> Hello > >> >> i need some precision about nipals in the chemometrics package in R . > >> >> > >> >> When i use nipals in chemometrics i obtain T and P matrix. > >> >> > >> >> I really don't understand what to do with these two matrix to obtain > >> >> the scores for every the component (like in spss fo example) > >> >> > >> >> Comp1 Comp2 Comp3 > >> >> quest1 0,8434 0,54333 0,3466 > >> >> quest2 0,665 0,7655 0,433 > >> >> > >> >> Thank you very much for your help > >> >> (I know that X=TP+E)... But don't understand else.... > >> >> > >> > > >> > [[alternative HTML version deleted]] > >> > > >> >______________________________________________ > >> >R-help@r-project.org mailing list > >> >https://stat.ethz.ch/mailman/listinfo/r-help > >> >PLEASE do read the posting guide > >> >http://www.R-project.org/posting-guide.html > >> >and provide commented, minimal, self-contained, reproducible code. > >> > >> > > > > [[alternative HTML version deleted]] > > > > > > ______________________________________________ > > R-help@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > > [[alternative HTML version deleted]]
______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
