ternary_transformation {ggtern}

Ternary / Cartesian Transformation

Description

Functions to transform data from the ternary to cartesian spaces and vice-versa.

Usage

tlr2xy(data, coord, ..., inverse = FALSE, scale = TRUE, drop = FALSE)

xy2tlr(data, coord, ..., inverse = FALSE, scale = TRUE)

Arguments

data

data.frame containing columns as required by the coordinate system. Data will be scaled so that the rows sum to unity, in the event that the user has provided data that does not.

coord

Coordinate system object, inheriting the CoordTern class, error will be thrown if a different coordinate system is sent to this method

...

not used

inverse

logical if we are doing a forward (FALSE) or reverse (TRUE) transformation

scale

logical as to whether the transformed coordinates are scaled (or reverse scaled in the case of inverse transformation) according to the training routine defined in the coordinate system.

drop

drop all non columns which are not involved in the transformation

Details

tlr2xy transforms from the ternary to cartesian spaces, an inverse transformation transforms between cartesian to ternary spaces

xy2tlr transforms from the cartesian to ternary spaces, an inverse transformation transforms between ternary to cartesian spaces, it is the reciprocal to tlr2xy, therefore an inverse transformation in xy2tlr function is the same as the forward transformation in tlr2xy

Author(s)

Nicholas Hamilton

Examples

data(Feldspar)
dfm = plyr::rename(Feldspar,c("Ab"="x","An"="y","Or"="z"))
crd = coord_tern()
fwd = tlr2xy(dfm,crd)
rev = tlr2xy(fwd,crd,inverse = TRUE)