Use r object in tikz chunk in Rmarkdown

Question

I'm trying to figure out to add R variables in a tikz chunk. Is there any way to achieve this.

Here is an example

---
output: pdf_document
---

```{r, echo = FALSE}
TEXT <- 1
```

```{tikz, echo = FALSE}
\begin{tikzpicture}
\node (x) at (0,0) {$x$};
\node (y) at (3,0) {$y$};
\draw[->] (x) to node [anchor = north] {`r TEXT`} (y);
\end{tikzpicture}
```

I would like the r TEXT to be replaced by whatever is in TEXT.

Answer 1

You don't actually need a tikz chunk, you can just load the package yourself:

---
output: pdf_document
header-includes:
  - \usepackage{tikz}
---

```{r, echo = FALSE}
TEXT <- 1
```

\begin{tikzpicture}
\node (x) at (0,0) {$x$};
\node (y) at (3,0) {$y$};
\draw[->] (x) to node [anchor = north] {`r TEXT`} (y);
\end{tikzpicture}