R DiagrammeR Flush Subscript and Superscript within Labels - r

Question

Long time reader, first time poster.
I am attempting to write mechner notation using DiagrammeR (through R Studio; everything is up to date; MacOS). Long term intention is to embed the code within a latex doc, but I'm taking this one step at a time. Currently, I cannot find the code necessary to force a subscript and superscript to be in-line with each other. So far, I have found this:
library(DiagrammeR)
grViz("
digraph dot {
graph [layout = dot, rankdir = LR]
node [fontname = Helvetica, shape = plaintext]
a [label = 'aA']
b [label = 'bA#_{2}#^{p}']
c [label = 'abC']
a -> b -> c
}")
Produces this.
But I need this.
I suppose the real question is how to properly format within those pesky quotations. I have yet to find a walkthrough on how to properly format (e.g., bold, italics, superscript) within the label field quotations. Suggestions?

Answer 1

I figured this out and forgot to post an answer! Here is the code that worked for me (Mac OSx; R Studio Sweave File, w/ pdfLaTeX enabled):
\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{matrix}
\newcommand{\1}{\textbf} %to save space
\begin{document}
\SweaveOpts{concordance=TRUE}
%example 1
\par{\centering
\begin{tikzpicture}
\matrix (m) [matrix of math nodes, nodes in empty cells, row
sep=1em,column sep=2em,minimum width=4em,nodes={anchor=center}]
{
a\1{A} & b\1{A}_{2}^{p} & ab\1{C} & \\
};
\draw [->] (m-1-1) -- (m-1-2);
\draw [->] (m-1-2) -- (m-1-3);
\end{tikzpicture}
\par}
%example 2
\par{\centering
\begin{tikzpicture}
\matrix (m) [matrix of math nodes, nodes in empty cells, row
sep=1em,column sep=2em,minimum width=4em,nodes={anchor=center}]
{
t\1{S}_{A}^{D} & s\1{R}_{CR} & t\1{S}_{CR} & \\
};
\draw [->] (m-1-1) -- (m-1-2);
\draw [->] (m-1-2) -- (m-1-3);
\end{tikzpicture}
\par}
\end{document}
Here is the output