fitsoilwater2: Interactive Estimation of the Groenevelt and Grant (2004)...

fitsoilwater2R Documentation

Interactive Estimation of the Groenevelt and Grant (2004) Model Parameters

Description

An interactive graphical adjustment of the soil water retention curve via Groenevelt and Grant (2004) formula. The nonlinear least-squares estimates can be achieved taking the graphical initial values.

Usage

fitsoilwater2(theta, x, x0 = 6.653, xlab = NULL, ylab = NULL, ...)

Arguments

theta

a numeric vector containing the values of soil water content.

x

a numeric vector containing pF (pore water suction) values. See soilwater2.

x0

the value of pF at which the soil water content becomes zero. The default is 6.653.

xlab

a label for the x axis; if is NULL, the label "pF" is used.

ylab

a label for the y axis; if is NULL, the label "Soil water content" is used.

...

further graphical arguments; see par.

Value

A plot of theta versus x and the curve of the current fitted model according to the adjusted parameters in an external interactive panel. Pressing the button "NLS estimates" a nls summary of the fitted model is printed on console whether convergence is achieved, otherwise a warning box of "No convergence" is shown.

Author(s)

Anderson Rodrigo da Silva <anderson.agro@hotmail.com>

References

Groenevelt & Grant (2004). A newmodel for the soil-water retention curve that solves the problem of residualwater contents. European Journal of Soil Science, 55:479-485.

See Also

nls, soilwater2, soilwater

Examples

w <- c(0.417, 0.354, 0.117, 0.048, 0.029, 0.017, 0.007, 0)
pF <- 0:7
fitsoilwater2(w, pF)

# End (not run)

soilphysics documentation built on June 7, 2022, 5:06 p.m.