auto-num-fig-tab-rmarkdown.Rmd

---
title: Auto Numbering Figures and Tables
subtitle: Rmarkdown
author: David Braze
email: davebraze@gmail.com
date: "`r format(Sys.time(), '%B %d, %Y')`"

fontsize: 11pt
geometry: margin=1in
header-includes:
  - \usepackage{booktabs}

output:
  bookdown::html_document2:
    number_sections: no
    highlight: tango
    toc: yes
    toc_depth: 2
    toc_float: yes

---

```{r setup}
library(knitr)
library(pander)
library(gt)

```

# Figure Numbering

In order for figure numbering to work, it is necessary to set the
chunk option `fig.cap`. You then refer to the code chunk containing 
the figure by name. See Figure \@ref(fig:fig-data-dist).

```{r fig-data-dist, fig.cap = 'This is a plot of random numbers.'}
## rmarkdown::render("test.Rmd")

x <- rnorm(100)
y <- x+rnorm(100)
plot(x,y)
```

# Table Numbering with knitr()

Referencing a table works a little differently from
Figures. There is no chunk option for Table captions. However, table referencing 
is otherwise similar to figure referencing in that you refer to the code chunk 
containing the table by name. See Table \@ref(tab:tab-kable). At the time I'm writing this,
it only works with `knitr::kable()`. Other table creating functions do aspire to add 
the capability.

```{r tab-kable}
## kable() handles table numbering internally. All tables in the same
## code chunk get the same number.

## Table 1
kable(head(iris), caption = "Iris with kable")
## Another Table 1 (ok, same chunk = same table)
kable(head(mtcars), caption = "Mtcars kable")
```

```{r tab-pander}
## pander doesn't magically handle table numbers. So, no table number here.

pander(head(iris), caption = "Iris with pander")
```

```{r tab-kable-2}
## Back to kable, so we get a numbered table
kable(head(mtcars), caption = "Mtcars kable")
```

```{r tab-gt}
## gt also doesn't automatically number tables.
gt(head(mtcars)) %>%
        tab_header(title="", subtitle="Mtcars gt::gt") %>%
        tab_options(table.width=pct(90),
                    table.border.top.style=0,
                    row.padding=px(4)) %>%
        tab_style(style=cells_styles(
                      text_align='left',
                      text_color='grey'),
                  locations=cells_title(groups="subtitle"))

```

# Table Numbering, other than kable()

With a little bit of pixie dust, we can get auto-numbering for pander
tables. See Table \@ref(tab:tab-pander-2).

```{r tab-pander-2}
## pander doesn't magically handle table numbers. So, no table number here.

pander(head(iris), caption = "(\\#tab:tab-pander-2) Iris with pander, now numbered.")
```

I'd hoped something like this would work with `gt::gt()`: Table
\@ref(tab:tab-gt-2). But, it does not. This issue is known to gt::gt()
developers. See issues on the gt github site listed here:
https://github.com/rstudio/gt/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+bookdown

```{r tab-gt-2}
## gt also doesn't automatically number tables.

gt(head(mtcars)) %>%
    tab_header(title="", subtitle="(\\#tab:tab-gt-2) Mtcars gt.") %>%
    tab_options(table.width=pct(90),
                    table.border.top.style=0,
                    row.padding=px(4)) %>%
        tab_style(style=cells_styles(
                      text_align='left',
                      text_color='grey'),
                  locations=cells_title(groups="subtitle"))

```