biplot {mva} | R Documentation |
Plot a biplot on the current graphics device.
biplot(x, ...) biplot.default(x, y, var.axes = TRUE, col, cex = rep(par("cex"), 2), xlabs = NULL, ylabs = NULL, expand = 1, xlim = NULL, ylim = NULL, arrow.len = 0.1, ...)
x |
The biplot , a fitted object. For biplot.default ,
the first set of points (a two-column matrix), usually associated
with observations. |
y |
The second set of points (a two-column matrix), usually associated with variables. |
var.axes |
If TRUE the second set of points have arrows
representing them as (unscaled) axes. |
col |
A vector of length 2 giving the colours for the first and second set of points respectively (and the corresponding axes). If a single colour is specified it will be used for both sets. |
cex |
The character expansion factor used for labelling the points. The labels can be of different sizes for the two sets by supplying a vector of length two. |
xlabs |
A vector of character strings to label the first set of
points: the default is to use the row dimname of x , or
1:n is the dimname is NULL . |
ylabs |
A vector of character strings to label the second set of
points: the default is to use the row dimname of y , or
1:n is the dimname is NULL . |
expand |
An expansion factor to apply when plotting the second set of points relative to the first. This can be used to get the two sets on to a physically comparable scale. |
arrow.len |
The length of the arrow heads on the axes plotted in
var.axes is true. The arrow head can be suppressed by
arrow.len = 0 . |
A biplot is plot which aims to represent both the observations and
variables of a matrix of multivariate data on the same plot. There are
many variations on biplots (see the references) and perhaps the most
widely used one is implemented by biplot.princomp
.
The function biplot.default
merely provides the
underlying code to plot two sets of variables on the same figure.
Graphical parameters can also be given to biplot
.
a plot is produced on the current graphics device.
B.D. Ripley
K. R. Gabriel (1971). The biplot graphical display of matrices with application to principal component analysis. Biometrika 58, 453-467.
J.C. Gower and D. J. Hand (1996). Biplots. Chapman & Hall.
biplot.princomp
, also for examples.