TT.add                  Function to add a new default package
                        parameters.
TT.baseplot             Internal. Create an empty plot scene for a
                        texture triangle.
TT.chemometrics.alr     Compute the additive log-ratio transformation
                        of compositional data.
TT.classes              Plot the texture classes polygons in a texture
                        triangle plot.
TT.classes.tbl          Returns the table of classes of a texture
                        classification system.
TT.contour              Wrapper for the contour() function adapted to
                        texture triangles.
TT.data.test            Test the validity of some soil texture data
                        table (3 particle size classes).
TT.data.test.X          Test the validity of some soil texture data
                        table (X particle size classes).
TT.dataset              Genetates a virtual cross correlated clay silt
                        sand + Z dataset.
TT.dia2phi              Convert a soil particle diameter dia
                        [micro-meters] into phi = -log2(dia/1000)
TT.geo.get              Retrieve and return the geometrical parameters
                        from a list of parameter values (NULL or not).
TT.get                  Function to retrieve / get the default package
                        parameters.
TT.grid                 Plot a grid at regular texture intervals inside
                        an existing soil texture triangle.
TT.image                Wrapper for the image() function adapted to
                        texture triangles.
TT.iwd                  Inverse weighted distance interpolation on a
                        grid.
TT.kde2d                Calculated the 2D probabilty density on an x-y
                        grid.
TT.locator              Interactive (mouse clic) retrieval the CLAY
                        SILT SAND coordinate of points on a texture
                        triangle.
TT.mahalanobis          Calculates the Mahalanobis distance between
                        clay silt and sand.
TT.normalise.sum        Normalises the sum of the 3 particle size
                        classes.
TT.normalise.sum.X      Normalises the sum of the X particle size
                        classes.
TT.plot                 Plot soil texture triangles / diagrams.
TT.points               Plot a soil texture data table as points on an
                        existing texture plot.
TT.points.in.classes    Classify a table of soil texture data according
                        to a soil texture triangle.
TT.set                  Function to change / set the default package
                        parameters.
TT.str                  Stretch or reshape the range of value of some
                        data set.
TT.text                 Plot text labels for each values of a soil
                        texture data table on an existing texture plot.
TT.text.transf          Log-linear transformation of a soil texture
                        data table between 2 particle size systems (3
                        classes).
TT.text.transf.X        Log-linear transformation of a soil texture
                        data table between 2 particle size systems (X
                        classes).
TT.vertices.plot        Plot the vertices of a texture classification
                        system.
TT.vertices.tbl         Returns the table of vertices of a texture
                        classification system.
soiltextureInfo         Display and / or export system and package
                        version information
soiltexture_gui         Text-based menu for plotting and classifying
                        soil texture data
