clo {compositions} | R Documentation |
Closes compositions to sum up to one (or an optional total), by dividing each part by the sum.
clo( X, parts=1:NCOL(oneOrDataset(X)),total=1)
X |
composition or dataset of compositions |
parts |
vector containing the indices xor names of the columns to be used |
total |
the total amount to which the compositions should be closed; either
a single number, or a numeric vector of length
gsi.getN(X) specifying a different total for each compositional vector in the dataset. |
The closure operation is given by
clo(x) := ( x_i / sum(x_j))
clo
makes a composition without assigning one of the
compositional classes acomp
or rcomp
.
Note that after computing the closed-to-one version, obtaining a
version closed to any other value is done by simple multiplication.
a composition or a datamatrix of compositions without compositional class. The individual compositions are forced to sum to 1 (or to the optionally-specified total). The result should have the same shape as the input (vector, row, matrix).
clo
can be used to unclass compositions.
Aitchison, J. (1986) The Statistical Analysis of Compositional Data Monographs on Statistics and Applied Probability. Chapman & Hall Ltd., London (UK). 416p.
(tmp <- clo(c(1,2,3))) clo(tmp,total=100) data(Hydrochem) cdata <- Hydrochem[,6:19] plot( clo(Hydrochem,8:9) ) # Giving points on a line