| idt {compositions} | R Documentation |
Compute the isometric default transform of a vector (or dataset) of compositions or amounts in the selected class.
idt(x)
## Default S3 method:
idt( x )
## S3 method for class 'acomp':
idt( x )
## S3 method for class 'rcomp':
idt( x )
## S3 method for class 'aplus':
idt( x )
## S3 method for class 'rplus':
idt( x )
## S3 method for class 'rmult':
idt( x )
## S3 method for class 'factor':
idt( x )
x |
a classed amount or composition, to be transformed with its isometric default transform |
The general idea of this package is to analyse the same data with
different geometric concepts, in a fashion as similar as possible. For each of the
four concepts there exists an isometric transform expressing the geometry
in a full-rank euclidean vector space. Such a transformation is computed by idt. For
acomp the transform is ilr, for
rcomp it is ipt, for
aplus it is ilt, and for
rplus it is iit. Keep in mind that the
transform does not keep the variable names, since there is no guaranteed
one-to-one relation between the original parts and each transformed variable.
A corresponding matrix of row-vectors containing the transforms.
K.Gerald v.d. Boogaart http://www.stat.boogaart.de
## Not run:
# the idt is defined by
idt <- function(x) UseMethod("idt",x)
idt.default <- function(x) x
idt.acomp <- function(x) ilr(x)
idt.rcomp <- function(x) ipt(x)
idt.aplus <- ilt
idt.rplus <- iit
## End(Not run)
idt(acomp(1:5))
idt(rcomp(1:5))