affy (version 1.50.0)

pca.legend: A Function to Automagically Place a Legend in a PCA Plot

Description

This function places a legend in a PCA plot depending on which corner is available. If there are no available corners, user intervention will be required. This is an internal function and not intended to be called by the end user.

Usage

pca.legend(pca, groups, groupnames, pch.df, x.coord = NULL, y.coord = NULL,
  saveup = FALSE)

Arguments

pca

A 'pca' object

groups

A vector of numbers indicating group membership

groupnames

A vector of names describing the different groups

pch.df

A numeric data.frame delineating the plotting symbols (column 1) and colors (column 2) to use

x.coord

X-coordinate for legend. Used if automatic placement will fail

y.coord

Y-coordinate for legend. Used if automatic placement will fail

saveup

Boolean: Save a small value for plotting additional text?

Value

• This function returns nothing. It is used only for the side effect of placing a legend in a plot.