show.soil.texture: Display points on a soil texture triangle.
Description
show.soil.texture displays points on the soil triangle plotted
by soil.texture as symbols. It is most useful for adding
new points to an existing plot.
Matrix of soil textures where each row is a
soil sample and three columns contain the proportions of the
components sand, silt and clay in the range 0 to 1 or the
percentages in the range 0 to 100.
pch
Symbols to use for plotting the observations.
col.symbols
Colors to use for plotting the observations.
bg.symbols
Fill colors for symbols.
show.legend
Logical - whether to show a legend. If there are more
than about six soil textures, it is probably better to add a legend
separately.
Value
A list of the x,y positions of the soil types plotted.
data(soils)
# first just show the soil triangle soil.texture(main="Soil Texture Triangle")
# now plot the observations show.soil.texture(soils,pch=2,col.symbols=2)