Calculate elements for the PCA biplot

This function performs calculations for the construction of a PCA biplot.

# S3 method for biplot
PCA(
  bp,
  dim.biplot = c(2, 1, 3),
  e.vects = 1:ncol(bp$X),
  group.aes = NULL,
  show.class.means = FALSE,
  correlation.biplot = FALSE
)

Arguments

bp

an object of class biplot obtained from preceding function biplot().

dim.biplot

the dimension of the biplot. Only values 1, 2 and 3 are accepted, with default 2.

e.vects

the vector indicating which eigenvectors (principal components) should be plotted in the biplot, with default 1:dim.biplot.

group.aes

a vector of the same length as the number of rows in the data matrix for differentiated aesthetics for samples.

show.class.means

a logical value indicating whether group means should be plotted in the biplot.

correlation.biplot

a logical value. If FALSE, the distances between sample points are optimally approximated in the biplot. If TRUE, the correlations between variables are optimally approximated by the cosine of the angles between axes. Default is FALSE.

Value

an object of class PCA, inherits from class biplot.

Examples

biplot(iris[,1:4]) |> PCA()
#> Object of class biplot, based on 150 samples and 4 variables.
#> 4 numeric variables.
# create a PCA biplot
biplot(data = iris) |> PCA() |> plot()