## Usage

ggbiplot(pcobj, choices = 1:2, scale = 1, pc.biplot =
TRUE, obs.scale = 1 - scale, var.scale = scale, groups =
NULL, ellipse = FALSE, ellipse.prob = 0.68, labels =
NULL, labels.size = 3, alpha = 1, var.axes = TRUE, circle
= FALSE, circle.prob = 0.69, varname.size = 3,
varname.adjust = 1.5, varname.abbrev = FALSE, ...)