This page describes the fitplc package, which can be used to fit curves to measurements of plant stem, leaf or root conductivity (or conductance) at varying water potentials (so called 'PLC curves').
The package either fits the Weibull curve as reparameterized by Ogle et al. (2009), or a sigmoidal model proposed by Pammenter and van Willigen (1998).
The package calculate confidence intervals for the parameters (e.g., P50, slope at P50) (using the bootstrap or normal approximations), make standard plots of 'relative conductivity' or the 'percentage embolized' vs. water potential (including a bootstrap 95% CI of the fit and the location of the P50).
Please read ?fitplc for more instructions, and the examples on that page.
To report bugs or suggest new features, please open a new issue by following this link.
The fitplc package is now on CRAN, so just do
install.packages("fitplc")
library(fitplc)
To install the development version, use this command:
library(devtools)
install_bitbucket("remkoduursma/fitplc")
library(fitplc)
Windows users must have Rtools installed for this to work.
Work in progress : options and implementation for the various models. 'when': is the confidence interval (via method 'ci') always calculated?
Model fitter ci when
Weibull nls confint always
boot bootci = TRUE
nlme intervals always
sigmoidal lm boot always
lme intervals always
loess loess boot always
nls_sigmoidal nls boot bootci = TRUE