R: Conversion Between PCA Classes

q2rPCA {ChemoSpec}

R Documentation

Conversion Between PCA Classes

Description

Utility to convert objects of S3 class prcomp (Q-mode PCA) to objects of S3 class princomp (R-mode PCA) or vice-versa. An internal function, not generally called by the user.

Usage

q2rPCA(x)

Arguments

`x`	An object of either class `prcomp` or class `princomp`. It will be converted to a form that can be used by functions expecting either class.

Details

In the conversion, the necessary list elements are added; the old elements are not deleted (and user added list elements are not affected). To indicate this, the class attribute is updated to include class conPCA. The new object can then be used by functions expecting either class prcomp or princomp. For details of the structure of prcomp or princomp, see their respective help pages.

Value

A list of class conPCA. Note that the order of the elements will vary depending upon the direction of conversion.

`loadings`	The loadings from `princomp`, or a copy of the rotations from `prcomp`.
`scores`	The scores from `princomp`, or a copy of the x values from `prcomp`.
`call`	The call. Objects of class `prcomp` do not store the original call, so a place holder is used. Otherwise the unchanged call from `princomp`.
`n.obs`	The number of observations from `princomp`, or computed from the 1st dimension of x in `prcomp`.
`class`	`conPCA` is pre-pended to the existing class.
`sdev`	Unchanged from original.
`center`	Unchanged from original.
`scale`	Unchanged from original.

Author(s)

Bryan A. Hanson, DePauw University.

References

https://github.com/bryanhanson/ChemoSpec