Brilliant! Thanks so much for the help!
-Scott On Mon, 14 Jun 2004, Prof Brian Ripley wrote: > Centring and scaling. The code is very easy to real, and contains > > x <- as.matrix(x) > x <- scale(x, center = center, scale = scale.) > > Note that the help page does say > > The calculation is done by a singular value decomposition of the > (centered and scaled) data matrix .... > > > On Mon, 14 Jun 2004, Scott Robbins Loarie wrote: > > > Thanks very much for showing me these functions, > > > > In prcomp(), the documentation says that Value: x is "the data > > multiplied by the 'rotation' matix". Using sample data: > > > > data(iris) > > iris<-as.matrix(iris[,1:4]) > > pcprim<-prcomp(iris, scale=TRUE) > > > > Why does iris%*%pcprim$rotation (the data multiplied by the rotation > > matrix) not equal pcprim$x? > > > > Thanks very much, > > > > Scott > > > > > > On Mon, 14 Jun 2004, Prof Brian Ripley wrote: > > > > > Why are you using the OPRHANED multiv library for a facility covered by > > > princomp() and prcomp() in base R? The list might be able to help you > > > with the latter, but no one is supporting multiv (hence its status). > > > > > > On Sun, 13 Jun 2004, Scott Robbins Loarie wrote: > > > > > > > I am having trouble using the pca function in the multiv library. > > > > I am trying to generate the values found in $rproj by using $evecs to > > > > calculate linear combinations of my input data. However, I have been not > > > > been able to correctly calculate the $rproj values. > > > > > > > > Using the following standard sample data, why does iris%*%pcprim$evecs[,] > > > > not equal pcprim$rproj? > > > > > > > > data(iris) > > > > iris<-as.matrix(iris[,1:4]) > > > > pcprim<-pca(iris) > > > > > > -- > > > Brian D. Ripley, [EMAIL PROTECTED] > > > Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ > > > University of Oxford, Tel: +44 1865 272861 (self) > > > 1 South Parks Road, +44 1865 272866 (PA) > > > Oxford OX1 3TG, UK Fax: +44 1865 272595 > > > > > > > > > -- > Brian D. Ripley, [EMAIL PROTECTED] > Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ > University of Oxford, Tel: +44 1865 272861 (self) > 1 South Parks Road, +44 1865 272866 (PA) > Oxford OX1 3TG, UK Fax: +44 1865 272595 > ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
