R version 2.11.1 (2010-05-31)
Copyright (C) 2010 The R Foundation for Statistical Computing
ISBN 3-900051-07-0

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> date()
[1] "Fri Feb 25 05:11:31 2011"
> ###################################################
> ### chunk number 2: int0
> ###################################################
> dpoints <- matrix(c(-1,-1,2,-1,2,1,1,2), byrow=T, ncol=2)
> colnames(dpoints) <- c("x","y")
> dpoints <- data.frame(dpoints)
> dpoints
   x  y
1 -1 -1
2  2 -1
3  2  1
4  1  2
> plot(dpoints,type="n")
> text(dpoints,lab=rownames(dpoints))
> abline(v=0, col=grey(0.6), lty=2)
> abline(h=0, col=grey(0.6), lty=2)
> 
> 
> ###################################################
> ### chunk number 3: int1
> ###################################################
> dptscent <- scale(dpoints, center=T, scale=F)
> plot(dptscent,type="n")
> text(dptscent,lab=rownames(dpoints))
> abline(v=0, col=grey(0.6), lty=2)
> abline(h=0, col=grey(0.6), lty=2)
> 
> 
> ###################################################
> ### chunk number 4: int2
> ###################################################
> dt <- dist(dptscent, method = "euclidean", diag = T, upper = T)
> round(dt, digit=4)
       1      2      3      4
1 0.0000 3.0000 3.6056 3.6056
2 3.0000 0.0000 2.0000 3.1623
3 3.6056 2.0000 0.0000 1.4142
4 3.6056 3.1623 1.4142 0.0000
> 
> 
> ###################################################
> ### chunk number 5: int3
> ###################################################
> matdt <- as.matrix(dt)
> matH <- -matdt*matdt/2
> matH <- t(matH-colMeans(matH)) - rowMeans(matH) + mean(matH)
> matH          
        1       2       3       4
1  5.5625 -0.4375 -2.9375 -2.1875
2 -0.4375  2.5625  0.0625 -2.1875
3 -2.9375  0.0625  1.5625  1.3125
4 -2.1875 -2.1875  1.3125  3.0625
> 
> 
> ###################################################
> ### chunk number 6: int4
> ###################################################
> library(ade4)

Attaching package: 'ade4'

The following object(s) are masked from 'package:base':

    within

> bicenter.wt(-0.5*matdt*matdt)
        1       2       3       4
1  5.5625 -0.4375 -2.9375 -2.1875
2 -0.4375  2.5625  0.0625 -2.1875
3 -2.9375  0.0625  1.5625  1.3125
4 -2.1875 -2.1875  1.3125  3.0625
> 
> 
> ###################################################
> ### chunk number 7: int5
> ###################################################
> eigen(matH)$values
[1]  8.409853e+00  4.340147e+00 -6.149595e-16 -1.776357e-15
> eigen(matH)$values[1:2] -> valpro
> 
> 
> ###################################################
> ### chunk number 8: int6
> ###################################################
> eigen(matH)$vectors[,1:2] -> vecpro
> norme <- function(x) sum(x*x)
> apply(vecpro,2,norme)
[1] 1 1
> t(vecpro)*sqrt(valpro)
          [,1]       [,2]       [,3]      [,4]
[1,] 2.2391581  0.3232505 -1.2157677 -1.346641
[2,] 0.7407234 -1.5678039 -0.2905322  1.117613
> vecpro <- t( t(vecpro)*sqrt(valpro))
> colnames(vecpro) <- c("vecteur1","veteur2")
> vecpro
       vecteur1    veteur2
[1,]  2.2391581  0.7407234
[2,]  0.3232505 -1.5678039
[3,] -1.2157677 -0.2905322
[4,] -1.3466409  1.1176127
> 
> 
> ###################################################
> ### chunk number 9: int7
> ###################################################
> plot(vecpro,type="n")
> text(vecpro,lab=rownames(dpoints))
> abline(v=0, col=grey(0.6), lty=2)
> abline(h=0, col=grey(0.6), lty=2)
> dist(vecpro, method = "euclidean", diag = T, upper = T)
         1        2        3        4
1 0.000000 3.000000 3.605551 3.605551
2 3.000000 0.000000 2.000000 3.162278
3 3.605551 2.000000 0.000000 1.414214
4 3.605551 3.162278 1.414214 0.000000
> 
> 
> ###################################################
> ### chunk number 10: int8
> ###################################################
> pco1 <- dudi.pco(dt, scannf=F, nf=2)
> scatter(pco1)
> 
> 
> 
> proc.time()
   user  system elapsed 
  0.424   0.052   0.474