在 `knitr` 中使用 `beamer_presentation` 选项不可能 cross-referring 图形和表格
Impossible to cross-referring figures and tables with `beamer_presentation` option in `knitr`
为什么 \@ref() 符号无法与 beamer-presentation 一起使用？
下面的问题可能会让你想起一些cross-reference编写PDF文档时的问题，例如，但是答案中介绍的方法在我制作 beamer-presentations 时对我没有帮助。
现在我很困惑，因为 \@ref(fig:label-to-refer-figure) 和 \@ref(tab:label-to-refer-table) 符号引用 figure/table 在我使用选项 output: beamer_presentation。如下图所示，cross-reference 的原始代码出现在输出的 PDF 文件中，我无法引用 figure/table 编号。尽管即使在列出的环境和纯文本字段中引用也很顺利，但是 cross-reference for figure/table number 没有正确生效。
我的环境
- R 版本 3.5.1 (2018-07-02)
- 平台：x86_64-w64-mingw32/x64（64 位）
- 运行 下：Windows 10 x64（内部版本 17134）
- knitr_1.20
- rmarkdown_1.10
- RStudio v1.2.1206（预览版）<- 我更喜欢这个 this reason
MWE
此处的 MWE I post 是从以下来源创建的：test-beamer.Rmd 和 myref.bib。
test-beamer.Rmd
---
title: "Test"
subtitle: |
| subtitle,
| with a line break
author: |
| CLR
| Rafael
institute: |
| Now I'm here,
| Now I'm there
date: "`r format(Sys.time(), '%Y/%b/%d')`" #English
output:
beamer_presentation:
keep_tex: yes
latex_engine: lualatex
theme: "AnnArbor"
colortheme: "dolphin"
fonttheme: "structurebold"
toc: true
#toc_depth: 3
#number_sections: TRUE
fig_caption: TRUE
dev: cairo_pdf
#extra_dependencies: subfig
citation_package: natbib
slide_level: 2
bibliography: bibs/myref.bib
biblio-style: apa
always_allow_html: yes
---
```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)
```
## The only thing
With Table \@ref(tab:under-pressure-table), @test-master shows that Figure \@ref(fig:under-pressure) depicts...
## Slide with Bullets in which I want to refer a figure
- \@ref(fig:under-pressure)
- @test-master
- \@ref(tab:under-pressure-table)
## Slide with R Output
```{r cars, echo = TRUE}
summary(cars)
```
## Slide with Plot
```{r under-pressure, fig.cap='Under Pressure', fig.pos='h', out.width="0.75\textwidth"}
plot(pressure)
```
## Slide with Table
```{r under-pressure-table, caption = "This is a table"}
knitr::kable(pressure)
```
## More extraordinary
With Table \@ref(tab:under-pressure-table), @test-master shows that Figure \@ref(fig:under-pressure) depicts...
编辑：我将 fig.cap='Under Pressure', fig.pos='h', out.width="0.75\textwidth" 添加到图形块，并将 caption = "This is a table" 添加到 knitr::kable()。如果没有这些代码，标题和 table/figure 数字都不会出现......但是，即使将它们提供给整个 .Rmd 文件，问题仍然存在，除非你执行@Yihui 的回答。
myref.bib
@master{test-master,
author = {Freddie Mercury and Brian May and John Deacon and Roger Taylor},
title = {Bohemian {R}hapsody: {W}e are the champions},
school = {{Queen}},
year = {2018},
address = {London}
}
\@ref() 符号仅是 bookdown 的一个功能。要将此功能移植到一般 R Markdown 文档，您可以设置特定 bookdown 输出格式的 base_format 选项，例如，
output:
bookdown::pdf_book:
base_format: rmarkdown::beamer_presentation
详情见Section 3.4 of the bookdown book。
适合本题MWE的完整yaml部分可能是这样的：
---
title: "Test"
subtitle: |
| subtitle,
| with a line break
author: |
| CLR
| Rafael
institute: |
| Now I'm here,
| Now I'm there
date: "`r format(Sys.time(), '%Y/%b/%d')`" #English
output:
bookdown::pdf_book:
base_format: "function(..., number_sections) rmarkdown::beamer_presentation(...)"
number_sections: true
keep_tex: yes
latex_engine: lualatex
theme: "AnnArbor"
colortheme: "dolphin"
fonttheme: "structurebold"
toc: true
fig_caption: TRUE
dev: cairo_pdf
#extra_dependencies: subfig
citation_package: natbib
slide_level: 2
bibliography: bibs/myref.bib
biblio-style: apa
always_allow_html: yes
---
为什么 \@ref() 符号无法与 beamer-presentation 一起使用？
下面的问题可能会让你想起一些cross-reference编写PDF文档时的问题，例如
现在我很困惑，因为 \@ref(fig:label-to-refer-figure) 和 \@ref(tab:label-to-refer-table) 符号引用 figure/table 在我使用选项 output: beamer_presentation。如下图所示，cross-reference 的原始代码出现在输出的 PDF 文件中，我无法引用 figure/table 编号。尽管即使在列出的环境和纯文本字段中引用也很顺利，但是 cross-reference for figure/table number 没有正确生效。
我的环境
- R 版本 3.5.1 (2018-07-02)
- 平台：x86_64-w64-mingw32/x64（64 位）
- 运行 下：Windows 10 x64（内部版本 17134）
- knitr_1.20
- rmarkdown_1.10
- RStudio v1.2.1206（预览版）<- 我更喜欢这个 this reason
MWE
此处的 MWE I post 是从以下来源创建的：test-beamer.Rmd 和 myref.bib。
test-beamer.Rmd
---
title: "Test"
subtitle: |
| subtitle,
| with a line break
author: |
| CLR
| Rafael
institute: |
| Now I'm here,
| Now I'm there
date: "`r format(Sys.time(), '%Y/%b/%d')`" #English
output:
beamer_presentation:
keep_tex: yes
latex_engine: lualatex
theme: "AnnArbor"
colortheme: "dolphin"
fonttheme: "structurebold"
toc: true
#toc_depth: 3
#number_sections: TRUE
fig_caption: TRUE
dev: cairo_pdf
#extra_dependencies: subfig
citation_package: natbib
slide_level: 2
bibliography: bibs/myref.bib
biblio-style: apa
always_allow_html: yes
---
```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)
```
## The only thing
With Table \@ref(tab:under-pressure-table), @test-master shows that Figure \@ref(fig:under-pressure) depicts...
## Slide with Bullets in which I want to refer a figure
- \@ref(fig:under-pressure)
- @test-master
- \@ref(tab:under-pressure-table)
## Slide with R Output
```{r cars, echo = TRUE}
summary(cars)
```
## Slide with Plot
```{r under-pressure, fig.cap='Under Pressure', fig.pos='h', out.width="0.75\textwidth"}
plot(pressure)
```
## Slide with Table
```{r under-pressure-table, caption = "This is a table"}
knitr::kable(pressure)
```
## More extraordinary
With Table \@ref(tab:under-pressure-table), @test-master shows that Figure \@ref(fig:under-pressure) depicts...
编辑：我将 fig.cap='Under Pressure', fig.pos='h', out.width="0.75\textwidth" 添加到图形块，并将 caption = "This is a table" 添加到 knitr::kable()。如果没有这些代码，标题和 table/figure 数字都不会出现......但是，即使将它们提供给整个 .Rmd 文件，问题仍然存在，除非你执行@Yihui 的回答。
myref.bib
@master{test-master,
author = {Freddie Mercury and Brian May and John Deacon and Roger Taylor},
title = {Bohemian {R}hapsody: {W}e are the champions},
school = {{Queen}},
year = {2018},
address = {London}
}
\@ref() 符号仅是 bookdown 的一个功能。要将此功能移植到一般 R Markdown 文档，您可以设置特定 bookdown 输出格式的 base_format 选项，例如，
output:
bookdown::pdf_book:
base_format: rmarkdown::beamer_presentation
详情见Section 3.4 of the bookdown book。
适合本题MWE的完整yaml部分可能是这样的：
---
title: "Test"
subtitle: |
| subtitle,
| with a line break
author: |
| CLR
| Rafael
institute: |
| Now I'm here,
| Now I'm there
date: "`r format(Sys.time(), '%Y/%b/%d')`" #English
output:
bookdown::pdf_book:
base_format: "function(..., number_sections) rmarkdown::beamer_presentation(...)"
number_sections: true
keep_tex: yes
latex_engine: lualatex
theme: "AnnArbor"
colortheme: "dolphin"
fonttheme: "structurebold"
toc: true
fig_caption: TRUE
dev: cairo_pdf
#extra_dependencies: subfig
citation_package: natbib
slide_level: 2
bibliography: bibs/myref.bib
biblio-style: apa
always_allow_html: yes
---