supcol function

Projections of Supplementary Columns

performs projections of supplementary columns.

supcol(x, ...)
## S3 method for class 'dudi'
supcol(x, Xsup, ...) 
## S3 method for class 'coa'
supcol(x, Xsup, ...)

Arguments

• x: an object used to select a method
• Xsup: an array with the supplementary columns (Xsup and x$tab have the same row number)
• ...: further arguments passed to or from other methods

Details

If supcol.dudi is used, the column vectors of Xsup are projected without prior modification onto the principal components of dudi with the scalar product associated to the row weightings of dudi.

Returns

A list of two components: - tabsup: data frame containing the array with the supplementary columns transformed or not

• cosup: data frame containing the coordinates of the supplementary projections

Author(s)

Daniel Chessel

Anne-Béatrice Dufour anne-beatrice.dufour@univ-lyon1.fr

Examples

data(rpjdl)
rpjdl.coa <- dudi.coa(rpjdl$fau, scan = FALSE, nf = 4)
rpjdl.coa$co[1:3, ]
supcol(rpjdl.coa, rpjdl$fau[, 1:3])$cosup  #the same

data(doubs)
dudi1 <- dudi.pca(doubs$fish, scal = FALSE, scan = FALSE)
if(adegraphicsLoaded()) {
  g1 <- s.arrow(dudi1$co, plot = FALSE)
  g2 <- s.arrow(supcol(dudi1, data.frame(scalewt(doubs$env)))$cosup, plab.cex = 2, plot = FALSE)
  G <- superpose(g1, g2, plot = TRUE)
  
} else {
  s.arrow(dudi1$co)
  s.arrow(supcol(dudi1, data.frame(scalewt(doubs$env)))$cosup, add.p = TRUE, clab = 2)
  symbols(0, 0, circles = 1, inches = FALSE, add = TRUE)
}