Thanks for the tip above, that answers the question of what to put in the YAML header, but knitting the document is not producing what I expect.
I have in my document:
```{r P4Lamp, fig.cap="Proc4 Dongle Architecture", out.height="25%", echo=FALSE}
knitr::include_graphics("Proc4-Lamp.png")
```
This generates the figure with the caption, but it is unnumbered. Also \@ref(fig:P4Lamp) does not resolve to a number.
Also, I'm trying to include and number listings:
I include the following:
::: {.example #P4 "Sample Message in P4 format"}
```{json, fig.cap="(ex:P4) Sample message in P4 format", eval=FALSE}
{
app: "ecd://epls.coe.fsu.edu/PP",
uid: "Student 1",
context: "SpiderWeb",
sender: "Evidence Identification",
mess: "Task Observables",
timestamp: "2018-10-22 18:30:43 EDT",
processed: false,
data:{
trophy: "gold",
solved: true,
objects: 10,
agents: ["ramp","ramp","springboard"],
solutionTime: {time:62.25, units:"secs"}
}
}
```
:::
```
But this does not add a caption, and `\@ref(exm:P4)` is not resolved.
So I think I'm missing a switch to turn on the cross reference engine.