plotrix (version 2.1-5)

get.triprop: Enter three proportion data - usually soil textures.

Description

get.triprop allows the user to enter triplets of proportions or percentages of three components such as sand, silt and clay in soils.

Usage

get.triprop(use.percentages=FALSE,cnames=c("1st","2nd","3rd"))

Arguments

use.percentages

Logical - whether to treat the entries as percentages and scale to proportions.

cnames

column names for the resulting three column matrix.

Value

• A matrix of the components of one or more observations.

Details

The three proportions of each row must sum to 100 or 1 within 1% or the function will warn the operator.

See Also

triax.plot, soil.texture

Examples

if(dev.interactive()) {
  # get some proportions
  newsp<-get.triprop()
  # show the triangle
  triax.frame(main="Test triax.plot")
  # now plot the observations
  triax.points(newsp)
 }