knitr plots, labels, and captions within one chunk - .Rmd files - r

Question

Jallen produced a solution for producing knitr plots, labels, and captions within one chunk - for Rnw files.
knitr plots, labels, and captions within one chunk
This works nicely for .Rnw but I can't make it work for .Rmd, don't see what is going wrong...
---
output:
pdf_document:
fig_caption: yes
fig_crop: no
---
```{r startup,echo=FALSE,results='hide',message=FALSE,tidy=FALSE,warning=FALSE,fig.keep='all',comment=NA}
require(knitr)
require(ggplot2)
opts_knit$set(progress = F, verbose = F)
opts_chunk$set(comment=NA,
tidy=FALSE,
warning=FALSE,
message=FALSE,
echo=FALSE,
dpi=600,
fig.width=6.75, fig.height=4, # Default figure widths
dev=c("pdf",'tiff'),
dev.args=list(pdf=list(NULL),tiff=list(compression='lzw')),
error=FALSE)
```
```{r plotloop,results='asis'}
for(x in seq(1,20)){
x1<-data.frame(x=seq(1,10),y=seq(1,10))
plt<-ggplot(data=x1,aes(x,y))+geom_point()
figLabel=paste('Figure',x,sep='')
capt<-paste('Caption for fig.',x)
cat(knit(text=(paste("```{r ",figLabel,",fig.pos='h',fig.cap='",capt,"'}\nplt\n```",sep=''))))
cat('\\newpage')

Answer 1

plot.knit function in knitr plots, labels, and captions within one chunk can be modified to account for the syntax of markdown as opposed to latex. plot.knit.md becomes
plot.knit.md<-function(chunkLabel,#text for chunk label which is also used for figure file name
capt,#text for caption
plt,
...)
{
cat(knit(text=knit_expand(text="```{r, {{chunkLabel}},eval=TRUE,fig.cap='{{capt}}',echo=FALSE}\nplt\n```"),
quiet=TRUE))
}
This works in the following markdown doc.
---
title: "plot.knit.md demo"
author: "Joel Allen"
date: "04/23/2015"
output:
html_document: default
pdf_document:
fig_caption: yes
---
This is an R Markdown document to demonstrate the generation of self-contained code chunks in a markdown file. It is particularly useful for situations where multiple plots are generated in a single code chunk allowing for dynamic label and caption support.
This example draws on
http://stackoverflow.com/questions/21685885/knitr-plots-labels-and-captions-within-one-chunk
in response to
https://stackoverflow.com/questions/27443019/knitr-plots-labels-and-captions-within-one-chunk-rmd-files
Items to note:
#. output pdf_document fig_caption option must be set to yes
#. plot.knit has been modified to plot.knit.md to account for the different syntax needed.
```{r, echo=FALSE,results='asis'}
plot.knit.md<-function(chunkLabel,#text for chunk label which is also used for figure file name
capt,#text for caption
plt,
...)
{
cat(knit(text=knit_expand(text="```{r, {{chunkLabel}},eval=TRUE,fig.cap='{{capt}}',echo=FALSE}\nplt\n```"),
quiet=TRUE))
}
require(ggplot2)
cars.p<-ggplot(cars,aes(x=speed,y=dist))+
geom_point()
plot.knit.md(chunkLabel="carsPlot",capt="this is a caption for the cars plot",plt=cars.p)
```
One thing to figure out though is the attachment of labels...