README.md

ellipse

ellipse contains ellipse drawing routines designed for pairwise confidence regions, including distorted ellipses for nonlinear regression regions. It also includes a routine plotcorr() for plotting correlation matrices using ellipses.

Installation

It is on CRAN, and can be installed using

install.packages("ellipse")

You can install the development version of ellipse from GitHub with:

# install.packages("devtools")
devtools::install_github("dmurdoch/ellipse")

Example

Plot approximate pairwise confidence regions and profile trace plots for a nonlinear fit:

data(Puromycin)
Purboth <- nls(formula = rate ~ ((Vm + delV * (state == "treated"))
   * conc)/(K + conc), data = Puromycin,
   start = list(Vm = 160, delV = 40, K = 0.05))
Pur.prof <- profile(Purboth)
ellipse::pairs(Pur.prof)

The plotcorr() function can plot a matrix of ellipses:

library(ellipse)
#> 
#> Attaching package: 'ellipse'
#> The following object is masked from 'package:graphics':
#> 
#>     pairs
corr.mtcars <- cor(mtcars)
ord <- order(corr.mtcars[1,])
xc <- corr.mtcars[ord, ord]
colors <- c("#A50F15","#DE2D26","#FB6A4A","#FCAE91","#FEE5D9","white",
            "#EFF3FF","#BDD7E7","#6BAED6","#3182BD","#08519C")   
plotcorr(xc, col=colors[5*xc + 6])