Ternary Plot

A ternary plot is a triangular diagram that displays proportions of three variables. It can be used to map three-dimensional data to a two-dimensional surface with the caveat that the data's original scales are lost (unless it was proportional data to begin with).#'

ternaryplot(x, data, ...)

# S3 method for formula
ternaryplot(x, data = NULL, response = NULL,
  groups = NULL, density = FALSE, region = density || !is.null(response),
  contour = density || !is.null(response), labels = !is.null(response),
  colorkey = region, xlab, ylab, zlab, xlim = c(-0.15, 1.15),
  ylim = c(-0.3, 1), panel = panel.ternaryplot,
  default.prepanel = lattice.getOption("prepanel.default.xyplot"),
  drop.unused.levels = lattice.getOption("drop.unused.levels"),
  subset = TRUE, ...)

# S3 method for data.frame
ternaryplot(x, data = NULL, ...)

# S3 method for matrix
ternaryplot(x, data = NULL, ...)

Arguments

x	See Methods (by class).
data	A data frame in which the formula, groups, and conditioning variables are evaluated.
...	Arguments that are passed on to other methods, particularly panel.ternaryplot().
response	An optional response variable
groups	A variable or expression to be evaluated in data and used to distinguish groups by varying graphical parameters.
density	Compute two-dimensional density estimates via MASS::kde2d().
region	Fill density or response estimates with a color gradient.
contour	Draw contour lines for density and response estimates.
labels	Label contour lines.
colorkey	if TRUE automatically computes a colorkey for density or response estimates. Can also be a list (see lattice::levelplot() for details on this).
xlab	X axis label (the left dimension)
ylab	Y axis label (the right dimension)
zlab	Z axis label (the top dimension)
xlim	X limits for the plot region.
ylim	Y limits for the plot region.
panel	The panel function.
default.prepanel	The default prepanel function.
drop.unused.levels	Drop unused conditioning or groups levels.
subset	An expression that evaluates to a logical or integer indexing vector. Like groups, it is evaluated in data. Only the resulting rows of data are used for the plot.

Value

An object of class "trellis". The update method can be used to update components of the object and the print method (usually called by default) will plot it on an appropriate plotting device.

Methods (by class)

• formula: A formula of the form top ~ left * right. Variables will be evaluated inside data if provided.

• data.frame: A data frame for which the first three columns will be mapped to the left, right, and top dimensions of the ternary plot respectively.

• matrix: A matrix for which the first three columns will be mapped to the left, right, and top dimensions of the ternary plot respectively.

Examples

ternaryplot(Fertility ~ Agriculture * Catholic, data = swiss)
ternaryplot(Catholic ~ Examination * Education, response = Infant.Mortality,
            data = swiss, contour = FALSE)

ternaryplot(Or ~ An * Ab | Feldspar, data = feldspar)

ternaryplot(Or ~ An * Ab, groups = Feldspar, data = feldspar, density = TRUE)