compositions (version 1.01-1)

gsigetBalStruct: An Auxiliary functions to compute user-defined ilr and ipt transforms.

Description

Parses the expressions for the balance functions.

Usage

gsi.getBalStruct(descr,names,allowMinus=FALSE,allowOne=FALSE)

Arguments

descr

the expression

names

character: the in the dataset

allowMinus

Wether to allow for - as a synonym for /

allowOne

Wether to allow 1 as a variable name resembling a constant.

Value

• provides a list of pairs giving the components in the Numerator and the Denominator of the balances.

Details

These functions will not be usually called on themselves, but through their wrappers, mainly balanceBase.

References

Egozcue J.J., V. Pawlowsky-Glahn, G. Mateu-Figueras and C. Barcel'o-Vidal (2003) Isometric logratio transformations for compositional data analysis. Mathematical Geology, 35(3) 279-300

See Also

ilrBase,ipt,ilr, http://ima.udg.es/Activitats/CoDaWork03

Examples

#gsi.getBalStruct(~A/B/C,c("A","B","C"))