Functions:
=========
bpca.default    Biplot for `data.frame' or `matrix' objects.
bpca.prcomp     Biplot for `prcomp' objects.
bpca            Main function (S3 based).
plot.bpca.2d    Plots `bpca.2d' objects with the package `graphics'.
plot.bpca.3d    Plots `bpca.3d' objects with the packages `scatterplot3d'
                (`graphics' based) and `rgl' (OpenGL based).
plot.qbpca      Plots `qbpca' objects with the package `graphics'.
qbpca           Evaluates the quality of the biplot representation for
                `bpca.2d' and `bpca.3d' objects.
summary.bpca    Summarizes `bpca' (`bpca.2d' and `bpca.3d') objects.
var.rbf         Calculates the matrix of graphical correlations projected by
                the biplot for `bpca.2d' and `bpca.3d' objects.
var.rdf         Calculates the matrix of `poor' graphical correlations,
                represented by the biplot, for `bpca.2d' and `bpca_3d'
                objects.
dt.tools        Calculates vector variable lengths, angles between vector
                variables and variable correlations from `data.frame' or
                `matrix' objects.

Datasets:
========
gabriel1971     Percentages of households having various facilities and
                appliances in East Jerusalem Arab areas, by quarters of
                the town.
gge2003         A didatic matrix of genotypes (rows) and environments
                (columns).
