Using GraphTerm with R

GraphTerm supports basic inline graphics display and the notebook interface using R. The file $GTERM_DIR/bin/gterm.R includes helper functions for using the GraphTerm API to display inline graphics. The following R packages need to be installed: RCurl, Cairo, and png. On Linux, the following additional libraries, or their equivalents, may need to be installed: libcurl4-openssl-dev libcairo2-dev libxt-dev. Here’s a plotting example:

$ R -q
install.packages(c("RCurl", "Cairo", "png"))  # The first time
gterm <- paste(Sys.getenv("GTERM_DIR"),"/bin/gterm.R", sep="")
source(gterm)          # Load GraphTerm API helper functions
g <- gcairo()          # Initialize Cairo device for GraphTerm output
x <- rnorm(100,0,1)
hist(x, col="blue")
g$frame()              # Display plot as inline image
hist(x, col="red")
g$frame(TRUE)          # Overwrite previous plot
hist(x, col="green")
g$frame()              # New plot

The notebook mode of GraphTerm will also work with R, without any additional software. GraphTerm can open Markdown files (in a format very similar to R-markdown) as a notebook, and also saves notebooks using the same format. The file $GTERM_DIR/notebooks/R-histogram.R.md contains a sample notebook displaying inline graphics (see Inline plotting with R). To open the notebook, click on it in the gls output, or use the notebook/open menu option after starting R.