princomp.rmult {compositions}R Documentation

Principal component analysis for real data

Description

Performs a principal component analysis for datasets of type rmult.

Usage

## S3 method for class 'rmult':
princomp(x,...)

Arguments

x a rmult-dataset
... Further arguments to call princomp.default

Details

The function just does princomp(unclass(x),...,scale=scale) and is only here for convenience.

Value

An object of type princomp with the following fields

sdev the standard deviation of the principal components.
loadings the matrix of variable loadings (i.e., a matrix whose columns contain the eigenvectors). This is of class "loadings".
center the mean that was substracted from the data set
scale the scaling applied to each variable
n.obs number of observations
scores if scores = TRUE, the scores of the supplied data on the principal components. Scores are coordinates in a basis given by the principal components.
call the matched call
na.action Not clearly understood

Author(s)

K.Gerald v.d. Boogaart http://www.stat.boogaart.de

See Also

princomp.rplus

Examples

data(SimulatedAmounts)
pc <- princomp(rmult(sa.lognormals5))
pc
summary(pc)
plot(pc) 
screeplot(pc)
screeplot(pc,type="l")
biplot(pc)
biplot(pc,choice=c(1,3))
loadings(pc)
plot(loadings(pc))
pc$sdev^2
cov(predict(pc,sa.lognormals5))

[Package compositions version 0.91-6 Index]