There are several options for integrating your R workspace with LaTeX. One of these is the R package `tikzDevice`

that allows you to export images created in R as tikz code in a .tex file, for immediate use in a LaTeX document via the line `\include{diagrams}`

.

A simpler way, the one we all start out with, is to export an image from R as a .pdf, then include it using the line `\includegraphics{diagrams.pdf}`

. This is a pretty easy and straightforward workflow – so, why would I want to use `tikzDevice`

?

There several advantages to converting your images into TikZ code directly from R:

- TikZ diagrams consist of vectors coded directly into your LaTeX document: there’s no loss of image resolution.
- The labels on TikZ diagrams match the font of your LaTeX document.
- Wonderful LaTeX equations can be effortlessly used as labels in your diagrams.
- You can harness the power of the loop in R to create a single .tex file containing many images.
- You can harness the power of the loop in R to add
`\caption{}`

and`\label{}`

lines to all your images for immediate reference within LaTeX. - You can include all these features and output via one line in LaTeX:
`\include{diagrams}`

.

## A Simple Example

That being said, let’s export a TikZ scatterplot using the `tikzDevice`

package. We will use data posted on Dr. Walter Enders web site.

#### R:

# gdata helps read .xls files require(gdata) df = read.xls("http://cba.ua.edu/assets/docs/wenders/arch.xls", sheet = 1) # tikzDevice will export the plots as a .tex file require(tikzDevice) # choose a name and path for the .tex file # folder should be the same as where your latex document resides tikz( '/Users/kevingoulding/latex_documents/thesis/plot_with_line.tex' ) plot(df, xlab = "$\\alpha_t + \\hat{\\beta}X_t$", ylab = "$Y_t$", main = "$Y_t = \\alpha_t + \\hat{\\beta}X_t$") abline(h = mean(df[,2]), col = "red", lwd = 2) dev.off() # must turn device off to complete .tex file

To include this diagram in your LaTeX document, simply add the line `\include{plot_with_line}`

and compile. Don’t forget to include `\usepackage{tikz}`

in the preamble. If you zoom in, you can see that we’ve labeled the plot and axes using LaTeX math language (amsmath).

A few things to be careful with as you try to code LaTeX equations from within R:

- All backslashes need to be doubled.
`\`

–>`\\`

. - All equations still need to be bordered by
`$`

on each side.

To be continued…