soiltexture (version 1.2.9)

TT.points.in.classes: Classify a table of soil texture data according to a soil texture triangle.

Description

The function calculate in which classe(s) of a texture triangle (classification system defined by 'class.sys') lies each soil sample (with texture data) in the table 'tri.data'. As a sample may lie inside a texture class, but also at the edge of 2 or more texture classes, the function does not only output one single texture class per sample. If 'PiC.type' is 'n' or 'l', it rather output a table where each column is a texture class and each row a texture sample, and yes / no information about the belonging of the sample to each texture class. Alternatively, If 'PiC.type' is 't'it will output a text string (per sample) containing all the texture classes to which that point belong. The texture data in 'tri.data' can be transformed into another particle size system prior to their classification if needed. See the options base.css.ps.lim, tri.css.ps.lim, dat.css.ps.lim, css.transf and text.transf.fun. ON DEFAULT VALUES OF TT.points.in.classes() ARGUMENTS? As TT.points.in.classes() shares its arguments with many other functions, their default value is not defined in TT.points.in.classes() source code, but rather in a dedicated list object called 'TT.par' and stored in the environment TT.env. The function TT.get() is used to retrieve the default value of the arguments defined in TT.par (see ?TT.get). For instance, to know the default value of 'class.sys', you can type TT.get("class.sys"). To set a different default value for a given argument in R, use TT.set() (see ?TT.set). For instance to change the default value of 'class.sys', type TT.set( "class.sys" = "USDA.TT" ).

Usage

TT.points.in.classes(tri.data,

class.sys = NULL,

PiC.type = NULL,

css.names = NULL,

text.sum = NULL,

base.css.ps.lim = NULL,

tri.css.ps.lim = NULL,

dat.css.ps.lim = NULL,

css.transf = NULL,

text.transf.fun = NULL,

trsf.add.opt1 = NULL,

trsf.add.opt2 = NULL,

text.tol = NULL,

tri.sum.tst = NULL,

tri.pos.tst = NULL,

collapse = NULL,

texture2xy = FALSE,

blr.tx = NULL,

blr.clock = NULL)

Arguments

tri.data

Data frame. Data frame containing the CLAY, SILT and SAND 'coordinates' of the texture data points to be classified The data frame can contain more column than needed (ignored). The data frame must have column named CLAY, SILT and SAND (uppercase

class.sys

Single text string. Text code of the texture classification system to be used for the classification of 'tri.data'. Possible values are "none" (no classification plotted), "USDA.TT" (USDA texture triangle), "FAO50.TT" (FAO texture triangle with a

PiC.type

Single character string. If equal to 'n', then a table of 0, 1, 2 or 3 is outputed (0 if the sample does not belong to a class, 1 if it does, 2 if it lies on an edge and 3 if it lies on a vertex). Notice that the accuracy of the classification is

css.names

Vector of 3 character strings. Name of the columns in 'tri.data' that contains the CLAY SILT and SAND values, respectively. If NULL, default c("CLAY","SILT","SAND") value is assumed. Not to be confused with 'css.lab' that defines the labels of th

text.sum

Single numerical. Sum of the 3 particle size classes for each texture value (fixed). The real sum of the 3 particle size classes in 'tri.data' should be >= text.sum * (1-text.tol) OR

base.css.ps.lim

Vector of 4 numericals. Particle size boundaries (upper and lower) of the 3 particle size classes (CLAY, SILT and SAND, starting from the lower size of CLAY particles, 0, to the upper size of the SAND particles, 2000), in micrometers, FOR THE BAS

tri.css.ps.lim

Vector of 4 numericals. Particle size boundaries (upper and lower) of the 3 particle size classes (CLAY, SILT and SAND, starting from the lower size of CLAY particles, 0, to the upper size of the SAND particles, 2000), in micrometers, FOR THE TEX

dat.css.ps.lim

Vector of 4 numericals. Particle size boundaries (upper and lower) of the 3 particle size classes (CLAY, SILT and SAND, starting from the lower size of CLAY particles, 0, to the upper size of the SAND particles, 2000), in micrometers, FOR THE TEX

css.transf

Single logical. Set to TRUE to transform the texture coordinates of the texture triangle ('class.sys') or the texture data ('tri.data') into the base particle size class limits. See 'base.css.ps.lim' for the base plot particle size class limits,

text.transf.fun

R function with the same argument names and same output as the function TT.text.transf(). 'text.transf.fun' is the function that transform the texture values from one system of particle class size limits to another. Only used if css.transf == TRU

trsf.add.opt1

Non pre-defined format. If the user specifies its own texture transformation function in 'text.transf.fun' (not TT.text.transf()), then he can use 'trsf.add.opt1' and 'trsf.add.opt1' as new, additional, argument for his function. So the format of

trsf.add.opt2

Non pre-defined format. If the user specifies its own texture transformation function in 'text.transf.fun' (not TT.text.transf()), then he can use 'trsf.add.opt1' and 'trsf.add.opt1' as new, additional, argument for his function. So the format of

text.tol

Single numerical. Tolerance on the sum of the 3 particle size classes. The real sum of the 3 particle size classes in 'tri.data' should be >= text.sum * (1-text.tol) OR

tri.sum.tst

Single logical. If TRUE (the default), the sum of the 3 texture classes of each texture value in 'tri.data' will be checked in regard to 'text.sum' and 'text.tol'. If FALSE, no test is done.

tri.pos.tst

Single logical. If TRUE (the default), the position of texture values in 'tri.data' are tested to check that they are not OUTSIDE the texture triangle (i.e. that some texture values may be negative).

collapse

Single character string. If PiC.type = "t" and a sample lie on the edge of 2 texture classes, then both will be outputed in a single character string, separated by 'collapse'. Example of output: [1] "C" "VF, F" "C" "C" "M"

texture2xy

Single logical. Set to FALSE to avoid any transformation of the texture data (trigonometric) prior to testure data classification. Setting to FALSE avoid some numerical accuracy problems when a point is on the border of a texture class.

blr.tx

Vector of 3 character strings. The 1st, 2nd and 3rd values must be either CLAY, SILT or SAND, and determines the particle size classes associated with the BOTTOM, LEFT and RIGHT axis, respectively. CLAY, SILT and SAND order in the vector is free,

blr.clock

Vector of logicals, eventually with NA values. Direction of increasing texture values on the BOTTOM, LEFT and RIGHT axis, respectively. A value of TRUE means that the axis direction is clockwise. A value of FALSE means that the axis direction is

Examples

require( "soiltexture" ) 



# Create a dummy data frame of soil textures:

my.text <- data.frame( 

    "CLAY"  = c(05,60,15,05,25,05,25,45,65,75,13,47), 

    "SILT"  = c(05,08,15,25,55,85,65,45,15,15,17,43), 

    "SAND"  = c(90,32,70,70,20,10,10,10,20,10,70,10), 

    "OC"    = c(20,14,15,05,12,15,07,21,25,30,05,28)  

)   #



# Display the table:

my.text



# Classify according to the FAO classification

TT.points.in.classes( 

    tri.data    = my.text[1:5,], 

    class.sys   = "FAO50.TT"  

)   #



# Classify according to the USDA classification

TT.points.in.classes( 

    tri.data    = my.text[1:5,], 

    class.sys   = "USDA.TT"  

)   #



# Classify according to the FAO classification, returns logicals

TT.points.in.classes( 

    tri.data    = my.text[1:5,], 

    class.sys   = "FAO50.TT", 

    PiC.type    = "l" 

)   #



# Classify according to the FAO classification, returns text

TT.points.in.classes( 

    tri.data    = my.text[1:5,], 

    class.sys   = "FAO50.TT", 

    PiC.type    = "t" 

)   #



# Classify according to the FAO classification, returns text, 

#   custom class separator in case of points belonging to 

#   several classes.

TT.points.in.classes( 

    tri.data    = my.text[1:5,], 

    class.sys   = "FAO50.TT", 

    PiC.type    = "t", 

    collapse    = ";"

)   #}